I can see this. I'm a licensed bartender, but not a great mixologist. I actually like tending bar at our YC.
I think the reality of this role is a lot less glamorous than you think, at least on the West coast. Lots of ocean deliveries on newly purchased old vessels, lots of mechanical issues, darned near zero sightseeing and fun and almost always under time pressure. For surprisingly little money.
Of the three, this is the one that offers the most potential income - but at the expense of an extremely short life for your skill set. Sure, there are businesses out there running outdated IT, but a lot of that is because they don't want to pay the cost of keeping up. And let's be honest, how smart would they be if they let some itinerant boating drifter in to their systems?
The good news is that today, and even more so in the future, IT skills will be cloud skills, which are the ultimate in portability. The bad news is they face the ultimate in competition - the entire ROW (rest of world).
To do the movable IT thing right I would recommend getting some sort of reputation in an area before retiring. Set up a blog, create original content, get followers, et cetera. In essence, all of that small business investment that you don't really want to do.
If you don't want to make that investment, that's fine - but then you might want to look at partnering with someone who has and would be willing to subcontract to you. They'll take a big chunk off the top up front, but then you won't have to look for work. Lots and lots of subcontractors out there.