Some things about black - it does show dirt and cobwebs, and you need a BUNCH of widely spread out high lumen fixtures, both above and below. It will also make the space look REALLY small... Friend of mine thought it would be cool to do the bedroom flat black, then have blacklights and posters... the effect should have been cool and bitchin, but you'd walk in there and it felt, well, opressive, like a morgue.
We helped paint it out once the fad had passed (and the cat was in treatment for depression, no ****!), we must have thrown at least half a dozen coats of "high opacity high coverage" on it before it started to cover. So be warned, it's kind of one of those things you have to commit to.
Also - I used to frequent a bar that did the upper foot and change of their place in flat black (from just below the fire risers up), and it DID look mighty cool, but when you looked up, you could see the cobwebs, dirt, etc. I asked the manager, she said they spent a couple days every few months going up there, cleaning it, touching up the black, etc... so yeah, you might be into extra maintenance. BTW, they put a ton into lighting, and it turned out OK, no idea what their power bill was, but when they turned on their maintenance lights, it worked.
However you go with it, good luck! Just because I wouldn't do it (mine is a working shop), doesn't mean you shouldn't, just go into it with your eyes open. My thought is now that they have those high lumen LED strip lights, you could run them along all the edges (even the floor edge) to enhance whatever lighting you otherwise install. The first time you drop your keys or wallet under your ride, you can thank me!!!