i'd go for a blood red, not as bright like fire engine, or candy apple.
blue is over rated, and plus, calmini have blue
then green, like someone said, john deere styles, or go a crimson or shamrock green. my vit was a modded version of shamrock green of some sort.
i dont think bright colours go too well.
maybe a gun metal grey or silver as well.
or how about pure white, like what a powder coat finish looks like?
be interesting to see how these all go.