So, although you've asked for someone else's opinions, you've ignored them and came up with what you could have done on your own?......... But, really, I'd go with silver. Really really. Cranks get scratched. Scratches remove colour and reveal the metal underneath (which happens to be silver). Coloured cranks only look good if you don't use the bike, otherwise, they get scratched and become *Rainbow colour* and silver. Whereas, silver cranks get scratched and become silver and silver!