The question usually is: Business or leisure? If it's for fun trying out something that's as different from the stack you're used to as possible (like Haskell o

The question usually is: Business or leisure? If it's for fun trying out something that's as different from the stack you're used to as possible (like Haskell or Lisp, for instance) will allow you to get the most out of the experience like learning new paradigms and gaining a different perspective on your favourite stack as well. As this is for business I'd say stick to what you know. Creating a useful software product that can be marketed successfully is difficult enough as it is. There's no need to complicate the process any further. Regarding hiring: First things first. You won't hire people in the beginning anyway I suppose. So, that's a problem you should consider later on. Besides, development lends itself to working remotely so area isn't really an issue anyway.