I'm not a fan of Belize. Everything exciting seems to be far away from the stop. I wouldn't venture out of Belize port very far without an excursion booked. Tendering seems to waste valuable time.
They have great snorkeling but so does Honduras and Cozumel. I'd like to see cruise lines start shuffling in a different port instead of Belize as I could go back to Honduras and Cozumel a few more times but Belize is a wasted stop for me.