Well, there are so many shows and events you can choose from! If it were me, then I'd choose to do (for big shows), dinner at Cinderella's at MK, and then watch Wishes from a romantic angle. In the middle of the trip you could take another big show at Fantasmic, but be sure to get there early if you don't have a dinner package.
For the last night, I highly suggest the dinner at Le Cellier and Illuminations after it--it'd be a ":')" moment.
But as for the rest of the trip--sit back, relax, and take as many breaks as possible to ensure that you two have the best time of your life and aren't tired when you're not supposed to be. You're on the Boardwalk, so take a walk around the Epcot resort land, it's a great place to walk around at night. Definitely coordinate something with the Bakery, and do whatever you have to do to make it the best days of your life, and when you come back with children you'll be able to fill them in on all that you loved about it.
Good luck, and if you need any further planning help (more in-depth), then I'll be here.