When I was on campus, they built the Samuel Riggs Alumni Center. I had walked through the garden a lot, but never been inside. The showcase was actually at Riggs, so we got to check it out. Since my friend and her fiance met at Maryland, it might be really cute if they got married there. Riggs is built to be a totally functional event space - their main ballroom is a pretty "typical" ballroom, with partitions.
The only problem I see with this is...you're still getting married in College Park. Campus is fun, but do you really want to have all your guests go after-party at the Fe? Wait, the Fe isn't even there anymore, is it? Also, hotel options are limited - there is the Marriott on campus, and a few other hotels around, but not great. If you're considering this location, also think about doing the wedding when school isn't in session - parking will be way easier, the hotels will probably be less full, and the campus won't be full of undergrads.
Images all from the Riggs Alumni Center Website.