This is a topic I intend to follow as it is something I have considered doing to keep me busy in retirement. There are several boats at my marina that rent themselves out for one reason or another, so obviously there are people who don't own a boat who would like to go for a sail.
I'm going to throw out some guesses based on what I see going on at Lake Grapevine, my home port. It would be great to hear from those with experience.
The people who are definitely raking it in are the "Party Boat" charters. Big double-deck houseboats with slides, obnoxiously loud sound systems, and all the comforts of shore. Ugh.
Of course, power boat rentals are popular, but pretty expensive.
I know a guy at my marina who charters his 36-footer for wedding photos, day sails, and the occasional overnighter. He provides what I would call the "Street Clothes" cruise - enjoying wine and cheese while drifting along peacefully with a skipper fully in charge and their needs catered to. I would think that this would call for a 32-foot or larger craft.
Then there are the "Sail Clubs". Although these are not technically "charters", there are several boats at my marina owned by the American Airlines Sailing Club, which makes it possible for people to get access to a boat to sail without the burdens of ownership. The Grapevine Sailing Club has a "Sail Away" program which is similar. Sailing proficiency is a requirement, so it's not something someone who walks in off the street can participate in.
Next, there's the "Sport Sail", for lack of a better term. I'm thinking boats under 32 feet, where passengers would be more actively engaged (i.e. as ballast), and drinks or snacks would have to wait until the boat is at anchor. I honestly don't see much of a market for this. Sail clubs, or just making friends with someone who has a sailboat and would like to have some company, would likely satisfy this need.
OTHOH, if like the OP, you are in a tourist mecca, it's possible that there would be those interested in just that sort of experience, but finding them (or them finding you) becomes the challenge. Partnering with local hotels, Air BNB's, Vrbo's, etc. might be a way to find customers. You would be able to price yourself below the Street Clothes cruisers, targeting a more adventuresome crowd.
As mentioned earlier, insurance and licensing will play into the "is it worth the expense and trouble" calculation.
Looking forward to hearing other's experience and thoughts...