Ooo yeah that'd be way pretty! i think that is what im going to do, either that or like a purple-ish color. i love when the sun is on either brunettes with red or purple in their hair, it looks super cool!
I would either do a red/ black. or keep with the espresso type brown.. i went from blond to deep brown to black, and wish i hadn't i'm goign to switch it back to deep brown
Unfortunately I can only see your avator picture, but even from that small picture I think you look beautiful as a brunette. I agree with black would be too harsh and I think the blonde would not look nearly as striking as the brown. You have a great exotic look with browns. If you're bored, luckily there's a lot of brown shades you can play with