Well, you are looking for the same things I am, and I think I'll probably end up in Mexico or Panama. I'm not as worried about over-touristed, but then over-touristed doesn't mean sex tourists in most of the world, which to me is one of the reasons I'm disillusioned with Thailand.

I've been everywhere but El Salvador in Central America. The problem there is that places are beign 'discovered' and prices are going up at unbelievable rates. And, except for Panama and Mexico, you aren't going to get the infrastructure you get in Thailand. Electricity can be unreliable, for instance.

Panama has a great retirement program, but Costa Rica has canceled theirs. I don't know how easily you get bored, but there is really nothing to do in the Cook Islands, and I don't think it is at all easy to emigrate there. The only other place I've been is Fiji, and they have political problems. And I don't think they are that open to immigrants, either.

Central American countries are quite corrupt, and many have high crime rates. I believe Nicaragua still has the lowest crime rate in Central America, meaning it is about the same as the US. In Honduras, it is common to solve property disputes by murdering your opponent.

I certainly think it is a good idea to visit some countries that interest you, but first you should check to see whether it is possible to move somewhere permanently. Some places, like Malaysia, have immigration programs, but also are willing to grant back-to-back tourist visas ad-infinitum.

My strongest recommendation would be that you not invest so heavily in a new place. Everyone should rent for at least a year, preferably two. From all the research I've done, I know that most expats don't last much more than two years.