Ur/Web hits every single one of your bullet points out of the park: http://www.impredicative.com/ur/
That said, I think it's big shortcoming to me (havent spent much time with it, spent ~10 minutes going through some of the demos) is that its a functional language. Personally, I don't mind haskell/sml/their ilk, but since I was trying to conceive of a language that people would actually use/adopt, it needs to be imperative and probably resemble something along the lines of C/php/python.