Congrats on your marriage; how long of a honeymoon are you planning? Seems like you can stay pretty much anywhere (Hawaii, NYC, Vegas, Niagara Falls, probably Paris, etc.) for one week on that budget. If you're planning a three week or longer honeymoon, money might start becoming a factor.
Probably be between 1 and 2 weeks. It would definitely not be Niagara Falls, as we've both been there numerous times (we live within a few hours drive), and it's lost its appeal since a friend of a friend jumped over recently. The fiance prefers no cruise, and I think she is (naturally) thinking it should be as cheap as possible.(I agree, but think it should be a trip that would be something to remember)
Sex. Sheesh, dude. If you haven't figured that one out, you've got no business getting married.
Riviera Maya.... we did the El Dorado Royale, all inclusive resort for adults only. Would definitely be in your price range.
I have two friends who just got married and went on a 3 week road trip across the western U.S., sounds like a really cool idea to me. Probably cheap.