Well, I've been playing for a few years, so probably should have asked this question from the beginning. Somewhere, I got the idea that all the offensive sets are about the same. Is that true? I seem to have better luck recruiting big men. Is there an offensive set that favors PF and C?

They are not the same. "About" the same. Eh, depends on who you ask. But I run each offense completely different.

You don't need great bigs to run a good flex offense necessarily. I'd never say to avoid flex since it's a personal favorite, but in your case, maybe use something else.

Triangle or Motion I would say. 40 passing with those bigs is a nice add on for both of these too.