I'm guessing you're not breeding for anything specific, so no breed standards apply.
Any roo that's mean to humans goes.
Any roo that's stalking a specific hen goes.
Any roo that's just too rough in general goes. This keeps in mind teenage roos are spazes when mating
A roo that moves out of my way when I'm in his space gets a plus.
A roo that calls hens over for treats and waits until they're done gets a plus.
A roo that drops his wing and dances for the hens gets two plus.
A roo that gives warning call gets a plus. More pluses if I can tell different warnings for different things approaching--i.e I have roosters that give different calls for my two different dogs. One dog is dead gentle and just walks around, the other likes to run through the flock and scatter them. Hence, different calls
After that, you could go with general personality, and of course color is a factor with roos. They're all so pretty!