I shoot for 5, and am content when I fall short at 4. At 3, I suspend the campaign until we can find another player. I've never tried 6+.

My players are rather system-lite, and are probably only playing Exalted to humor me (they'd play other roleplaying systems and it would fit their system proclivity better, I imagine). I've sold them on the world, though, so I can get them to show up for a good story.

I'm the opposite. I love a good, crunchy system that has lots of systems to hang exception-based effects like Charms upon, like a well decorated Christmas tree....