It looks alright, but there are still some things you could do to make it better.. in my opinion at least.
First... keep the black if you want, it should be fine. If you don't want the black contrasting too much, go with a dark purple/green. Then, take the grey you have now, lower the contrast (it looks too grainy at the moment) and switch the wall to a mixture of either blue and purple, or blue and green, depending on your preferenece really. It should look alright. I see one of the shades is already slightly blue, but it needs a bit more saturation and a more neutral blue.
Crit'd to death.
