Most of my snakes seem to enjoy not being around me, or being touched by me, or being looked-at by me. So i try to leave them be as much as possible.
If i think one is getting a little weird or agressive when I go in to change water and clean up, then I'll try to handle that one a bit more....i'm mainly talking about my MBK here. He's a punk sometimes.
I handle my ball python, rosy boa and bullsnake the most. These particular snakes seem not to get stressed out (they don't squirm around and start breathing fast). Also, my bullsnake and bp are my biggest snakes so far. I'd like to keep my "big ones" handleable. And the rosy is a freaking sweetheart. I sincerely believe he enjoys being outside his cage more than any of the other snakes i own.