As using vim involves switching between command and insert mode a lot, you end up reaching for the Escape key often—too often for my fingers.
You change your Escape key for Caps Lock. I was using C-c for the Escape key, which is a default alternative in vim. C-[ appears to be a old time short-cut, too.
But they all suffer from the same problems: moving your fingers away from the home row, and holding down the Ctl key in two of the approaches. And I hate doing both those things.
I stumbled across this excellent solution on a forum recently though: