I won't say much about the fun and sightseeing, but I'd like to remind you to be safe when island hopping. It's best to learn how to use the snorkeling equipment in advance. Most tour guides speak English, and many people go into the water before learning how to do it, which makes them choke easily.
Be sure to wear a life jacket. When getting on and off the boat, children and the elderly should pay attention to the gap between the boat and the dock.
In addition, the projects of each island hopping tour are exactly the same, so just choose the cheaper one. D'tour is very good.