Donovan plays with starters lmao he should not have a negative rating regardless.
Let's explain this to you:
#1 - you think Rudy is our best player, much better than Don, and is who we should build around
#2 - Conley and Rudy play most of their minutes together and many of those minutes are against the opponent's 2nd unit
#3 - that means Don is not playing with Rudy or Conley and is playing many of his minutes without Rudy against the opponent's 1st unit (best players)
So Don is playing without your wonder boy Rudy against the other team's best players. And your argument is that Don gets to play with better teammates? WHAT?
If Rudy is as good as you say he is, then Don is at a severe disadvantage playing against our opponent's 1st team. Of course his +/- will be less. He's having to do more against tougher competition with lesser teammates.