Congrats, I'm not sure I can be much help but there are currently some good engagment threads open...there are all sorts of ideas out there. The thing I would suggest is to get the "JUST ENGAGED" pins for town hall either before or right after the event and wear them throughout your trip! You never know when you'll get a few mickey mouse ice cream! I think the important thing is to do something that is special to you two! Good Luck.