Depending on your level of comfort, you can go to many places in SE Asia and live on next to nothing. For example, in Bali you can go to the more remote places, get a mile of perfect black or white sand beach to yourself, and pay anything from $2 a day for spartan accomodations, $20 for a room with breakfast and A/C, or $500 with your own personal servant.

Similar places can be found in Thailand, Malaysia, and other spots in Indonesia. Personally, I hated the Caribbean, and would avoid it like the plague. Also consider that if you are paying $75 a day for similar standards in the Caribbean than you are paying $25 a day for in SE Asia, your difference in airfare will be made up very quickly. Just an opinion.