Given Mitchell’s first two seasons, his future looks very promising (in which OP predicted a potential finals run). It’s not too hard to imagine Mitchell doing better than three All-star games and two All-NBA appearances.
If you’re going to compare players entire careers against Mitchell’s, than AK47, Boozer, DWill, Memo, Hayward, and Rudy are all definitely ahead.
The point is Mitchell has the ability to have a better career, hence the prediction.