We have been to Belize 4 times now over the past 10 years and we have found something new and amazing to do each time.
We have gone on X-Stream Cave Tubing and Zipline which was simple AWESOME. We did X-Stream Cave Tubing our first time there and the second time we did the combo and brought our kids to experience it with us.
We have also gone to Lamanai Mayan Ruins
and it was so worth the trip. The ruins and the wildlife are out of this world!
The last time we went to Goff's Caye with Belize Cruise Excursions and it was a beautiful mini island. We got to snorkel and hang out on the beach. There is a small barbecue restaurant and bar which was so cool.
I think you should definitely venture into Belize, so much to see and do!