Before I begin (oh, and buckle in, 'cause this is a doozy, or just skip to the bottom for a summary), this definitely isn't a suggestion for the near term future, as I know there's a lot of tickets that need to be addressed before this could be given any consideration, but that being said, I'd like to introduce three new suggestions that would all work in tandem: Player Character, Player Loyalty/Leadership, and Team Cohesion/Chemistry.

Player Character Attribute

This would exist on a separate tab or field on the player's page, or as an addition to the attribute list. These could either be tabulated exactly the same as physical/positional atts on a 0-100 scale, or via a notation/descriptive scale (Extremely High/Low Character, Very …, etc).

Character: Players with high character will help increase locker room cohesion/chemistry, as well as building their own Loyalty/Leadership rating at a much faster pace. Conversely, players with low character contribute and gain less in both those two fields, in addition to being at higher risk for off-field incidents that may result in potential issues such as suspensions or simply causing a distraction that results in a temporary hit (slowly improving over time) to their team's chemistry/cohesion (which could be significantly mitigated by immediately cutting the player—and possibly also the addition of in-house suspensions being implemented that could grant a smaller reprieve to this penalty).

Off field incidents would have a % chance of triggering every spin (with a major increase for most incident types happening over the early off-season spins). Examples being substance abuse (failed drug test, DUI, arrest, etc), PED use, diva personality (causing a hit to team chemistry week to week if they feel they weren't playing a significant enough role in that game), 'mercenary' personality (dramatically reducing their ability to generate leadership/loyalty for any given team, with maybe the added impact of having them slightly under-performing after landing a deal and receiving a slight boost during contract seasons), ‘locker-room cancer’ (negatively affecting team cohesion/chemistry, especially after big losses), ‘uncoachable’ (no or limited loyalty/leadership gains from coaching staff and slower learning of the playbook), ‘dirty player’ (higher chance of drawing roughing the passer, hitting a defenseless player, late hit, unsportsmanlike conduct, or unnecessary roughness penalties), and other general off-field issues (ie domestic abuse, sexual assault, shooting yourself in the leg at a night club, Riley Coopering, etc).

With every 'incident' a player has, it will also have a % chance of forming or exacerbating (or in some cases, especially on a team with high cohesion, taking it as a learning moment, and reducing) a negative habit in that arena, especially if no punitive action is taken where applicable, with a number of players coming out of the draft with pre-existing negative habits of varying degrees (the chance being determined by their initial character score). Possessing a negative habit will dramatically increase the likelihood of an incident occurring in the affected area compared to a player with a comparable character att but no negative habit in that area (ie a player like Josh Gordon is very likely to have an incident involving substance abuse, but not as likely to have other off field issues, whereas someone like Richie Incognito would be more of the ‘locker-room cancer’ type but unlikely to be running a dog fighting ring and so on).

Whether or not a player possesses a negative habit would be hidden information, with only an ‘incident report’ available somewhere on their player profile or under a 'scouting' tab on their card, so that users would have to come to their own conclusions on individual players based off their history. Does this draft prospect or player with two prior DUIs have a trend of bad decisions, or were they just flukes? With time and in a constructive environment, will they mature and mend their past issues? Then again, a player generated with low character may not have been gen’d with any negative habits at all, with consequently a low chance of ever having an ‘incident’ occur (although they will generate significantly less team cohesion for your team than someone with a better character score).

Character will tend to improve with the player’s age (maturity matters!), the rate at which will be further influenced by their Team Cohesion.

Player Loyalty/Leadership

Each player would start with a baseline in this, but it would overall be a very fluidic att, changing for each player based off environment and circumstances. Drafting the player would give them a significant bonus to this attribute (but only for that team; if they get cut/traded/released this will not roll over to their new squad). Time itself of course will gradually build up loyalty/leadership as well, so the longer they're with a team the greater their affinity and connection to the organization will be. Wins/losses could also have a small impact (can you blame a player for wanting to leave for a winning program?). Coaches will also build loyalty over time (maybe influenced by a new coaching Leadership attribute*, therefore giving coaches more function beyond just aiding player progression) for all those in their position groups (ie a head coach will affect all players, OC only offense, LB coach only LBs, etc).

Thus coach retention will affect the players, as any loyalty that coach produced for an individual player will be lost if they move on, but will be granted to the new team that hires them if they eventually make a bid for them in FA/trade for them, thus in a small way encouraging the real life phenomenon of players following coaches to new teams. It would also promote team’s promoting from within (currently a terrible GM decision to make since it voids one of your staff slots, rather than mining from off an opponent) since none of the players in their position group would lose that coach's accumulated influence on them.

Players with a high loyalty/leadership score will additionally be more likely to re-sign with their current squad at a 'home team discount' (although this would be relatively marginal). Conversely, those with a low score would be much more motivated by getting a payday, no matter where it might come.

Most importantly, players with a high enough loyalty/leadership score will grant a significant bonus to your team's overall cohesion/chemistry, and those with particularly low character will contribute little to nothing to it.

When a player is a cut, they’ll lose entirely any draft bonus they had and coaching bonuses (unless later reunited, of course), but will retain some portion of the leadership value they gained from time elapsing, so will still have value as leaders when transitioning to a new team.

Team Cohesion/Chemistry

This would be calculated by each position group, defense/offense, and as an overall for the whole team, the average of the three being the true number for each player (so the team cohesion value for the o-line starting three new rookies might be much lower than for an LB corps starting three savvy veterans).

Team Cohesion/Chemistry will impact as a % multiplier for how rapidly loyalty/leadership is accrued in players over time; a team with a toxic locker room will not engender much loyalty for those who come into it. Team cohesion will also adjust all players’ character scores; so a tight locker room with strong leadership will temporarily improve everyone’s character on the roster, making them less likely to get into mischief. A team with a bad chemistry/cohesion will detract from everyone’s character score, potentially exacerbating existing character concerns (ie Cleveland with Manziel and Gordon). Over time a player’s character may even shift towards whichever end of the spectrum their team is at, and some players will be more likely to reform and shake an existing negative habit if in a supportive environment. For instance, if Player A with 35 character joins a squad with high team cohesion, after 5 seasons in the league he may improve with age and influence up to say 50 while also reducing his negative substance abuse habit from a medium to low severity ranking, whereas if he’d joined a team with bad cohesion he may have not have improved at all in that time frame, and may even have worsened to a severe negative substance abuse habit.

This could also have a mild influence for gains in practice and on field performance, with a higher weight being placed on the player’s position group, then the overall defense/offense, and no weight given at all for the overall team cohesion in determining this (research shows, for instance, that consistency is one of the biggest determining factors in the success of an offensive line; the more players play together and can direct each other, the better they play as a unit). This is already factored in somewhat with each player’s knowledge of the playbook, so it wouldn’t necessarily be a huge adjustment.

With every spin, except for the pre-training camp off-season (and post-season for teams not involved), each individual player will contribute to this score either positively, negatively, or not at all. The higher a player’s Loyalty/Leadership, the more they contribute. If a player is cut/traded/not resigned by a team, their weekly contributions to the team’s cohesion will not only be lost, but the current team cohesion will take a small temporary hit based off of their overall per-spin contribution (so think carefully before axing your veterans, as it may ruffle some feathers!).

It was also suggested in a separate thread that player captains be implemented. If so, this could provide a very small % increase to that player’s contribution.

So how would this impact the game? TL/DR

Players with high character will gain loyalty/leadership faster over time, so as veterans their contributions will be significant in building your team’s cohesion and keeping it positive. This will be even higher the longer they’ve been on your team (team loyalty bonus) and in the same system (coach bonus); however, even a high character vet off the street can prove to be a big boon to a young team without established leaders. This will put higher value on keeping and starting team leaders, even past their prime (think Urlacher and Briggs on the Bears, or Polamalu and Harrison on the Steelers, all of whom were kept past their peak for this very reason). Another obvious example of the real-life importance for leadership is the fact that Josh McCown (who has received rave reviews about his character/leadership everywhere he’s played) has a shockingly high-paying job right now while Michael Vick still hasn’t had any offers, despite being unquestionably the better athlete.

Also, teams with a strong locker room may not shy away from giving a player with significant character concerns a second shot (like the Patriots frequently do), whereas a younger or leadership-lacking team may struggle taking on players with troubled histories. I think it’ll also serve to give individual players more personality as well, and increase the sense of a user truly being a GM and making hard calls on parting with team leaders or signing talented but risky prospects.

Overall, I’d say that it’d be better to have the number of off-field incidents be very low, and having low character players' primary deficit being their lack of leadership growth and consequent contribution to the team cohesion rating.

*Maybe (?) additionally include a ‘Coaching Style’ that would only come into play for Head Coaches, with three (or more that I’m not considering?) options: ‘Player’s Coach’ (granting a bonus to your weighting when signing FAs and overall Team Cohesion), Neutral/None/Balanced, and ‘Disciplinarian/Harsh/No Nonsense/What-have-you’ that would have a very minor negative to the overall Team Cohesion rating, but would decrease the rate of off-field incidents and increase the chance of 'reforming' players over time by reducing their negative habits.

Great read Ares, well done.
I really like these ideas and had some similar thoughts myself. I also think you could add in the fanbase to chemistry as well. Crowd noise is already part of the game, so maybe this isn't too far away.
Nice forward thinking though :)

I can't think of anything worse than "off field events" based on a hidden attribute affecting my team.

I wouldn't want a 'hidden' attribute, but what if there was some kind of indicator on both the team page and the player box, like there are for all the other attributes now?
You might have a great player but with a seriously bad attitude that affects the team negatively, conversely you might have an ordinary player who is a locker room legend.
I'd like this for coaches in particular, say an attribute called 'Inspiration', the more the coach has the more of a % - bonus the team would get.

Negative attitudes/team chemistry would be ok with me but not "off field events" resulting in suspensions.

Starting QB suspended for DUI...in the year you're really going for it, nah I wouldn't be a fan of that aspect either

Well there's already a chance of your starting QB tearing his ACL in the year you're "going for it" so why shouldn't there be a small chance of a character issue as well?

Injuries are part of the actual match.

yet again the off field events could be weighted very low especially for players that start, but that's just what i think. personally, i like the idea, the idea reminds me of how Russell Wilson shows his chemistry and leadership with the Seahawks, and that's kind of how the Hawks became the team they are today

Great post and love all of those suggestions.

Chemistry / Cohesion should be felt on game day. A group of Linebackers who have played together for a few seasons, will know each other and how to react as a group.