Well you'll be too early for the NAIAS...La Shish is pretty good and fairly authentic, although still fairly commercial...smaller family owned joints tend to be better sometimes. If you like sushi, check out Crave which just opened a couple of weeks ago...I believe the head chef is someone pulled from Nobu! They also have one of the best up and coming local DJs spinning on Thursdays I think.
as for downtown...you can check out the DIA, the Opera House, CPOP, Hard Rock, Greektown, 3 casinos...a decent amount of things to fill your night with.