There definitely needs to be a Team Chemistry or Morale system and development traits. Like if you bring in a higher rated player, it should drop a player's morale.
When it comes to the Transfer Portal, I just think there needs to be clear logic about it, unlike real life. Attach the players Recruiting Pitch preferences to a players profile. So based on the players highest preference, it'll cause them to want to transfer. So, if a players thinks he's not going to start, HC leaves, team isn't competitive enough, better opportunity, then it'll cause them to transfer or not. I do want to see backups on powerhouses transfer to 3-4 star schools in order to get a starting job. Just like, I want to see high rated players on lower schools transfer to a powerhouse if they're guaranteed a starting job.
My main question is how NIL is going to be use. I really don't want it to be like NBA2K where they just flood you with brands. But, I don't know if doing the lazy way by just making it a recruiting pitch is good enough either.