Since the car is gloss and you want everything to flow, I would suggest having it done in gloss black, unless you plan on doing a lot of matte black accents to tie it in. I like to keep with a theme, personally.

I wanted to do my entire black coupe in matte, but when I realized that i would probably not like it in a few years, I reconsidered. I think the matte black/gray accents belong on a car that is not gloss black, but that is just my opinion.

Good luck with it, they sure are fun (except the constant cleaning, only reason I went to graphite metallic)