The reason I don't regret being a Christian, is because I was exposed to a lifestyle that many others will not experience. I get to look back and say "well that was a silly point in my life". You do too (not that I'm trying to give advice). Learning that the "rules are made up and the points don't matter" is really all there is too it. I didn't even think about this, I don't mind mediocrity to be honest, but mediocrity forced on me because of a guilt I didn't deserve nor ask for, that is not for me. I could have lived the most terrifying existence I can imagine. Complete and utter mediocrity.
I guess I was never a 'happy' Christian, so I have a hard time looking back at my struggles with that faith positively. I always had problems with, and never drew much comfort from, the magic sky wizard. My faith was a continual source of stress, self-doubt/hate, and rigorous study.