Spring Break 2008

I am brand new to Thorn Tree and would love some experienced advice for where to go as Seniors in college for spring break this coming year. Here are some of our broad preferences:
1. Caribbean (warmth/beach)
2. all inclusive resort (or so we think, so the vacation doesn't get too crazy w/ people wanting to do different things at various times)
3. not dirt cheap in a dangerous location .... but not too expensive.
4. people our age + good nightlife

Thanks!