I was at an event this evening at Landmarc, a great restaurant at the Time Warner Center in New York City. As I was chatting with the event manager he mentioned that a lot of couples host their pre-wedding parties at the space and then he mentioned an idea for the post-wedding brunch.
Why limit the time you have the morning after your wedding from 10-12 when most guests, as well as the bride and groom, maybe sleeping in late after your reception and after party, and possibly fighting a hangover.
Make your post-wedding brunch open house style and serve a breakfast/luncheon buffet so guests can come and go as they please and you will have a leisurely time visiting with them.