Sea Strutter...You make excellent points. Even if you can't go "globe-trotting" on a small boat you can go lots of places most people don't and enjoy life a bit before "settling down". If you can live in a camper type R/V without complaint for a year or so...a boat is not much different!
I think it is easy to go cruising when you are quite young or ready to retire. It is much harder when you have a good career, kids, house, parents to take care of etc. ... so if you don't want to wait another 30 years or so and the idea sounds appealing...go before life ties you down. Just remember that it will be that much harder to work and settle down once you return!
You'll be miserable till you're 60!!