Are you changing rotors and calipers? Or, keeping what's already there? If the former, go the biggest you can reasonably.

If the latter, get the largest diameter booster you can fit.

I personally like large rotors/calipers. You can stop my car with just your big toe and no booster installed. I don't like booster assist brakes - personal preference. Oh, and I sat the wife in the rod once! She said it was claustrophobic and never came back! Just the way I like it!