I agree with you as to the language (I just like Python a whole lot better than JS), but I always feel dirty writing in a non-native language, not to mention the pretty big commitment one makes when choosing a transpiler.

In Transcrypt's case, the commitment probably isn't that big, since the JS source is pretty readable (and so I can just migrate to that relatively easily if I want to), but it's still a bit of a hack.

That said, it looks like a great project, and I'll definitely give it a try and hopefully use it more widely.