I'm really benefitting from this thread, thanks to all. I want to change out the BB and cranks on my Brompton. The goals is aesthetics, naturally but most importantly: weight reduction. What is the classiest-looking, but functionally lightweight combo? Currently running 6 sp (3 sp Sram hub + 2 sprockets). I've seen Zipp carbon, but it's not so pretty. Any suggestions? Thank you!