So true - I'm not sure what I expected. It always comes down to the fact that:

a) There is no intelligent auto-complete (not compared to an real IDE)

b) Background tasks of compiling/testing will block the UI. With scala especially, this is an issue.

c) No comparable refactoring capability.

I once had high hopes that eclim would be the answer, but I think it's just the wrong tool for the job. Let's not pretend vim can be something it was never designed for.

Neovim however might help to solve this problems, but when that will see the light of day, it seems to be hard to find out.