Jk for the win!!! (Also jj works well to).
I also set my mapleader to <Space> you would be surprised how useful that is. Not to mention , (comma) is a valid and useful vi movement key.
I have literally never found myself needing to pause to wait for a k and then a j. What are these words with "kj" in them that you're wary of? I'm genuinely curious :)
However my vim set up maps jk, kj, jj, and kk to Esc to in reality it is safe to just mash those two keys and one of the maps will work.