Elementary wants to be “the Apple of Linux”, to attract less-technical users and switchers from other OSes. Their development philosophy is similarly top-down: someone sets a “vision” and a small group of people gets to implement it. If you are a coder and you value bottom-up development, you should really look elsewhere.

Plus, most people don’t know most languages, so no matter what you choose, most devs have a language barrier. Vala, again, is very easy to pick up — certainly easier than C or C++ and probably easier than Java/C#/D.