I originally pondered that, but with the aesthetics of Kamino, I realize that it looked best to have the clones be white. Though on the other hand, what if Jango was fully white at first to call back to the Supertrooper armor? I pretty much like Phase I and II equally because of how smooth the transition was from the original clones to Stormtroopers, but I'll go with Phase I because it provided a good starting point, without being too similar or dissimilar to the Stormtroopers (yet still evoking the "good guy" feel). I like how the clones went from being personalized in Ep. III to identical in Ep. IV. It really shows how impersonal the Empire has become.