i wana build a 2.1 i want some low comp pistons but does any1 recomend any?also does it really matter what comp ratio i pick from the start?

also what sort of power are the standard rods good for but im not too bothered if i have to fit farndon ones or sumats!

the big question is the crank would it be ok to just have the standar one lightened and balanced?cus i would say a steel one would cost a bomb!

also any advice about building a 2.1 would be much appreciated!