What caterers are you using or have experienced at other events? Our venue (The National Nuclear Science and History Museum) will let us bring in any licensed caterer we choose, so we've got a lot of options.
The museum highly recommends Blue Plate Special, but they're at the very top of our price range. We're thinking about the Cooperage since we'd need to hire our alcohol servers through them anyhow (and we both love Scarpas). I'm open to any suggestions, though!