There is a decent Rasta presence here, and as Islander said, a Rasta "settlement" of sorts in the west end (Bordeaux). I hiked around there once and it did remind me of parts of rural Jamaica that I've visited like the Blue Mountains and Cockpit Country. That said, this small area is about the only truly rural part of our small island.
It would help if you could say more about your lifestyle and the things you are looking for. Also, where in Jamaica are you coming from? As someone who's spent time in both Jamaica and St. Thomas I'd say one of the more striking contrasts is that St. Thomas feels so much more crowded, more hectic, more Americanized. That's not to say that Greater Kingston is not crowded and hectic, but at least in Jamaica you still have expansive rural areas when you want a break from the hustle and bustle. St. Thomas has a definite West Indian flavor but not one that is as strong or all-pervading as you find in Jamaica. It is not as West Indian as I expected it to be or wanted it to be. I like to think of the VI as a land of mixture and compromise more than anything else. Lots of different peoples and influences crammed into a small space.
There is certainly crime on St. Thomas, but it does not pose nearly the threat to one's safety that you might experience in parts of Kingston for example. We have slum neighborhoods but not war zones. There is more order and the rule of law is generally upheld (though of course not by stateside standards). Economically you'd probably fare better here, just being part of the United States and earning US rather than Jamaican dollars. As I said this is a place of mixture and compromise. I highly recommend coming for a long scouting mission before you make any serious plans.
Also, what is your immigration status? My brother-in-law is Jamaican and had quite a time jumping through all the hoops when he left the country several years ago.