Which pair is better for CBS system?
Sully and Amir while decent on the defensive end/rebounding department provide little to no spacing on the offensive end. Teams are laying off of them/daring them to shoot. While focusing on our other undersized starters.
No doubt Zeller and Bass are not better as Sully and Amir but that pair last season worked better with what CBS wants to do out there.
I don't think Zeller and Bass really made the team any better than the Sully/Amir line-up does. Probably the opposite, but I don't have the stats in front of me.
The thing is, if you think that teams are laying off Sully and Amir on the perimeter is a major problem, the Bass/Zeller combo would be even worse in that regard. Zeller played really efficiently as a pick and roll guy last year, but even his mid-range shot is suspect. His inability to hit the mid-range is a big part of why he hasn't played much this year. Bass extended his reliable mid-range out to 3 at times, but he wasn't much better of a shooter than Sully is. The Amir/Sully combo has certainly been an upgrade over the Bass/Zeller combo. Better defense, better spacing, a lot better passing and rebounding. Sullinger has been solid all year. Amir has been good defensively but can make a bigger impact, IMO.
The important thing is how well the other guys play. Sully/Amir have been pretty consistent in what they bring every night. If they're your best starting option (debatable, but reasonable), then you have to be able to reliably score in other ways. If Thomas is the only one we can rely on to score consistently, were gonna have problems against better teams. Bradley and Olynyk need to have some actions run for them to get open shots. Crowder needs to keep hitting his 3's and I think we need to start pushing Jerebko and Lee to the end of the bench and maybe giving Hunter and Young a few minutes to see if they can hit some shots.
Our recent poor play, or our very good play that came before it, don't hinge on the performance of the Sully/Amir combo. They've been fairly consistent on both sides of the ball, especially Sullinger. Certainly better off with just about any combo of bigs we have than the Zeller/Bass pairing. Our recent poor play has everything to do with our suddenly not-so-suffocating perimeter D and our lack of consistent scoring from guys were relying on to score.