Here's my perspective of the team from last year
PG- Probably about the same. I don't think Mo Williams comes in and lights things on fire, but he won't have to. As long as he hits open 3's, thats what we need from him.
SG- Better by subtraction. No CJ, no Bell, which means more minutes for Burks. If we get post allstar break Hayward all season, much better.
SF- Our best SF was an undrafted rookie... (if you don't count Hayward) Williams is a big improvement. Carrolle should improve as well.
PF- This depends on Favors improvement and playing time. I wish we could get Milsap to come off the bench, he would dominate, and would be the #1 scoring option without AJ being a black hole.
C- Kanters improvement as the backup should be enough to consider it an improvement. If AJ is traded, its probably a step back, but I think we'd make 2 steps forward for 2013-2014.
I'm not convinced that Mo Williams is that much better than Harris. I think he can be though. What he gives us is a legitimate starting PG so we could trade Harris and get an actual SF,