1) Diving, while clear, was not as good as some of the other places we've been (e.g. MLE, GBR, DPS, etc). That said, visibility was great and it's definitely better than snorkeling.
2) Yes, we did. Assuming you're referring to Thalasso, yes, they were totally fine. They served it wherever we wanted without issue.
3) Definitely rent a moped and bike around the island. Only real way to get a feel for it, IMO.
What a tease. When I saw @ajk post here, I was sure it was a new installment