bucutie - it sounds like you and I are in the same boat! I have very dark hair and very light skin. I've been highlighting & coloring my hair forever, mostly because it is very thick and if I don't do something to brighten it it looks like a dead pelt on my head. My highlights/color have been burgundy, copper, honey brown and every colour in between. And I've NEVER done anything with my (black) brows, other than pluck them, and they look fine. I have a good friend who owns a salon and believe me, she would tell me if I needed to bleach them!
I feel lucky that I've never had to mess with them - seeing someone who needs to "put their eyebrows on" who hasn't can be scary. Leave them alone, trust me.