Black is boring, especially with all the other black components I have. Now I say this with an all-black speaker set. Though, if you have to have black, I do like the piano black approach. If done well, it's very snazzy.
I definitely prefer the richer deeper dark woods, but not particularly oak. Rosewood is particularly beautiful. Mahogany can look very nice too.
The challenge that I see, is that if you go for the exotic woods, it either needs to be a very, very good imitation or the real thing. A bad veneer is worse than a boring veneer.