What is the players opinion of you? How do I raise it and what does it effect?

It's exactly what it sounds like, it's your players opinion of you. Most are neutral or happy, but if a player is unhappy, most likely it's due to a lack of playing time. If you want to make that player happy give him more playing time.

Sometimes you'll see a player listed as livid. That's worse than unhappy and probably means you cut or traded the player, although those can also simply be unhappy.

Those opinions of you stick with that player even once off your roster. There have been players I wanted to resign off the free agent list but a pop up says "This player is unwilling to sign with you". If you have any former players on another roster, when you click on their team the opinion of you button reflects their opinion of you, even though they are no longer your player.

The lower their default ratings the quicker they will change thier minds. Slow as it is already

Okay that makes sense, I was just wondering if it effected a players effectiveness when playing any or not

No it’s just tied to contract negotiations. Another way to distribute talent

The only - ONLY - time I've seen this make any functional difference in the game is when a player is Livid at you. This only happens when you trade someone, and they will never not be livid at you. So you will never get to re-sign players that you trade no matter if they get cut or traded back to your team.

I've been unable to re-sign a player who was unhappy with me due to his lack of playing time. I had to start him in a few games to get him back to neutral before the end of the season.