Congratulations and happy planning! I'm sure that you will find the perfect place to have your wedding. I think it might come down to what is going to be more important, the date or the place. If you set on that date, I would try looking at Mexico, Costa Rica, Panama. If the date isn't as important, then I would work with the coordinator at the Punta Cana hotel and get a date that will work for your number of guests. If you are looking for villas, try homeaway.com and vrbo.com. They have great houses of different sizes, etc. available for rent.