Unity (C#) / Cocos2D (C++) I've released apps in RubyMotion and am currently making apps in Swift, however, I don't really see these languages as good fits for

Unity (C#) / Cocos2D (C++) I've released apps in RubyMotion and am currently making apps in Swift, however, I don't really see these languages as good fits for game dev, I guess it depends on what kind of games you want to make, and whether you want performance or ubiquity of your codebase. C++ will give you performance and ubiquity (Cocos2D), Unity is a little slower but runs everywhere. I'd worry far more about finding cross platform libs than the language. Find the libs, write in whatever languages work best with the libs. Also, do you want a job making games (use whatever employers use), or do you want to be an indie dev? If it's just for learning a language, flip a coin.