I favor the 3-2 straight up. If I have two guards with totally awesome speed and defense then I may use 2-3. And, of course, if the opponent strongly favors going inside or outside then that is most important. But I start my thinking with the 3-2 in mind.
The 3-2 not only lowers opponents 3Pt% but lowers his attempts. And don't forge the long 2's! A team like yours sort of funnels everything inside to your big shot blockers regardless if they're running motion and adapting or they see your 3-2 and deliberately go inside. Besides your guys tiring slower you are also committing fewer fouls. So, 3-2 defends the perimeter- forcing guys to drive - where the guy puts it up and, if your lucky it's blocked, but at least he seldom gets a "and one". The slower your guys are the fouls will inch up, and IQ the same. My rule of thumb over a season is I'm content when my FTM are greater than opponents FTA.
Unrelated... My end of year team stats often show advantages in all shooting %'s. Asst's/TO's/Blk's on the good side. And REB at least even. And yet my opponents will always be taking a lot more shots. I think the discrepancy is the different amount of rebounds available on defensive/offensive ends. In other words, my defense is great and forcing missed shots - and because it's the defensive end I will get most of the rebounds - but just not as much as a team playing man. I guess what I'm saying is people hear zone sucks at rebounding but then they use it and the rebounding stats seem ok. It's not. Zone really does suck at rebounding.