There's lots to see & do, enough that I have actually shopped dedicated vacations to Playa del Carmen. Yes, there are some ruins & things but there's also a couple adventure parks. I've seen at least 1 episode of House Hunters International done in Playa. Lots to do & see.
My husband sold his boat (19.5 ft bass boat) in October. We've been out on the lake when the winds kick up 8 footers. Talk about a wild ride! The front would dive in and submarine. When my youngest was about 12 or so they took a big hit & my hubby & brother snagged him as he was flying out of his seat. All that said, not 1 of us ever got sick. But! We were not enclosed. That's what worries me. Being enclosed. I suppose I could always get the patch for us to use that day. I got seasick 1 time when I was a teenager. First time out on the ocean in my friend's dad's 55' sailboat. We were under sail in 8 - 10 ft. seas. I was down in the cabin & got sick. Once I was sick it was a done deal. Pure misery. I remember it enough to know I never EVER want to feel that way again.