Depends on the circumstances:
Seychelles or the Caribbean for a sun bathing holiday,
Constantinople (Istanbul, if you are a heretic) because I would like to see the city of the world's desire,
Japan, because it's weird, and it's Japan.
Right now I would go sun bathing if I could (Finnish winter? no ty!)
That would also be amazing, I've always wanted to just hop on a train (or just drive a nice car) and ride around Europe
Ibiza sounds terrible; I've been to large and "popular" clubs in the south before, good luck getting in with any money in your pockets unless you are a supermodel..
Much prefer smaller clubs or bars. But I guess thats also up to your tastes (I can imagine the music in Ibiza being far better though)