To me, Sully fits way better than Bass with KG, and Bass fits better with the hulking Darko than wide-bodied Sullinger.
Bass has already proven that he can not play effectively inside and isn't much or a rebounder. Bass is very good at what he does - shoot open 17 footers. Unfortunately, that's what KG is also good at offensively at the tail end of his career.
Sully will get a ton of cheapie baskets with the starters, along with good offensive rebounding opportunities. Whatever defensive deficiencies he might have as a first year player can be better masked by playing with better players on the first team, including THREE who are at the top defensively for their position, in RR, AB and KG.
Bass will benefit by being the only jump shooting big on the second unit, and will also benefit from playing with a center and SF with great size. I'll take Bass, Darko, Green, Lee and JET as a second unit over any other in the league.