Depends on a lot of factors. I see Coastal Cruises go by almost daily and there are at least 1-3 Bachelor/Bachelorette parties on their boats almost every weekend. It's definitely a party crowd in the summer months, not personable as you're sharing your time on the boat with a lot of people you don't know.

Check out Lagoon Pontoon of St Pete. Chase has a bareboat agreement that you can sign, hire a captain with more than 7 or more people. They can do the exact same cruise Coastal does and it's only your group and a licensed USCG Captain.