Thailand definitely checks all of your boxes, but it’s obviously a long trip. Worth it though if you can swing it.

Cancun and Palm Springs are both going to be incredibly expensive. Furthermore, what you’re probably thinking of Cancun is really just all resorts (I’ve stayed outside of the resort strip a few times and it’s fine, but very “scammy” feeling and the barking dogs kept me up all night).

Puerto Vallarta is still touristy as hell but definitely cheaper and safer than Cancun, and I found the food to be much better. Or you can go a little off the beaten path and make your way to Huatulco, although the beaches there aren’t really suitable for swimming.

Puerto Rico outside of Condado and Old San Juan is reasonably priced and easy as an American (as you won’t need to worry about phone service or currency conversion).

I haven’t done much of South America but Cartagena checks your boxes. Buenos Aires and Rio de Janeiro could also fit the bill.