I think a cool but useless attribute to add (like passing) would be a gaming skill and a gaming frequency.

Gaming Skill = A player's ability to play video games well. 0 means they play horribly, 99 means they could be a professional esports player
Gaming Frequency = How often a player plays videogames. 0 means they rarely play, 99 means they are constantly playing

Now, how would this affect the sim? Gaming Skill would increase the morale of the player as it improves. The player wins more video games and is in a better mood because of a higher gaming skill. However, gaming frequency can have a negative effect on players. If it's at around 70 the player would get an optimal morale boost, but any higher would start having negative effects on the player. Players would start staying up too late playing video games, and missing practices and sometimes even games. Team's would have the option of banning video games completely, or on the road, or only at home.