I think the Python 2 vs. Python 3 is a real issue, I wouldn't hold that up as a great example.
I would like to see pygame more active. I know people have done work with GUI toolkits, better collision detection, and things like that. SDL 2.0 adds some easy wins, like being able to scale image textures easily and actually have transparency working. But it would be a large undertaking to get this working. I think Marcus has a great start with the ctypes shell on SDL. We need work to put a viable nice alternative on top of it.