I think we've settled on a rehearsal dinner venue, the Greek Islands Restaurant in Downtown Indianapolis. It's one of the few resaurants we've actually been to since moving the Indy and man, was it good! We've got a meeting set up for early April to talk about menus and such, but it seems like they're able to work in our price range and are accustomed to groups of this size (around 30-35 people.)
For those of your whose tastes run on the conservative side, don't worry, I think you'll find Greek food very accessible. It's kind of like Italian but without the tomato sauce, rice instead of pasta, and feta cheese instead of mozzarella. But the flavors are generally mild (not spicy) and the food is light and fresh. Ideal for a summer evening.
Good thing it's lunch time because now I'm hungry!