Not too blonde otherwise it looks unhealthy, but I really like what you did in the picture!

I think deep cobalt blue streaks look really cool in black hair, but they have to be done well by a professional.

I like a deep brown through black hair. I think those colors look really stylish together!

I like a nice neutral caramel through black hair. Make sure it isn't too warm. Reds can looks good too as far as contrast but I think that look is a little dated. If you wanted something more wild you could even do pale blond pieces. But if you, go this route, Id recommend to beep them under the top layer for more of a peek a boo look to prevent it from looking too streaky or zebra looking.

I really like the brown, (light) streaks through black hair. You could do red too but I think the brown looks great!

brown or tinted red looks nice:)