I never write from concept. The beat is the beginning, and then I fill in the rest of the song into what it should be.
It would probably take me an hour to two to write it down, get the feel of it, and that's with quite a few changes. It's not really a hard thing for me to do.
Models now need to promote themselves, think like businesswomen and diversify their careers by doing other things. Chances are very slim that a mere model will become a household name today.