Wow! Already! So excited for you!!
Everyone was able to make reservations at restaurants while we were there. I highly recommend the Italian at the Golf Course. You can call the restaurant to make the reservations. We walked right into other restaurants sometimes with groups of 12 and they accommodated us! I wouldn't worry about making those reservations ahead of time.
Excursions and spa should be booked ahead of time. They fill up really fast and if you have a busy wedding week schedule then your guests may be limited on the days they can actually enjoy an excursion off property. Most of the excursions are alllll day. Make sure people know that they should bring water, bug spray,a nd lots of sun block. Its hot and a lot of walking.
When you check in you will get a large resort map. Its way better than the PDF versions found online. Also, go to the public relations desk by the concierge and ask for a weekly activities guide. It will give you a list of times and days that shows and other activities are offered on the whole property!! Its like a jackpot for people who just want to stay on property and enjoy themselves!!
Have a fantastic time!! Can't wait to hear all about it