I'm a vim user as well, and I'm actually shocked at how many users apparently still use the ESC key. I actually didn't know any regular vim users did that, because to me, it seems super inefficient. I don't say that as a put-down or anything like that. But if you use vim, I'd highly recommend remapping caps lock to Esc. I think you will get used to it within a day and will never go back.
I'm a long-time vim user, and I use the esc for two reasons. First, because it's critical muscle memory, and if I go to a machine that is not my own don't want to be crippled. I would still consider remapping caps lock (as opposed to .vimrc remapping) since that would work when ssh'ed into arbitrary machines, but the problem there is I'm already using it for control, and because the control key is resized on the laptop keyboard I can't develop normal muscle memory when moving between different apple keyboards.
Personally I think people make way too big a deal about the escape key being difficult to hit. It's right there in the corner, never been a problem for me.
I've tried ctrl-c, ctrl-[, and ESC. The one that stuck for me was ESC. The others usually don't work in other programs that use vim keybindings.
Many people already map capslock to ctrl. You could map ctrl to ESC, but then it gets uncomfortable when switching computers, and it goes against 10+ years of muscle memory.
I tried remapping capslock once, but it got too confusing when switching computers.
I am a developer who writes code while in tmux and vim. I have remapped my Caps Lock key so it's Ctrl when presses with another key and Escape when pressed on it's own.
