I really don't like chord like shortcuts, while ctrl and [ are positioned in a way you don't have to contort your hand it kind of requires you to move away from the hjkl row or stretch your pinkies. Consider mapping esc to jk (as a sequence) it works surprisingly well.

  inoremap jk <esc> 

and

  inoremap <esc> <nop>

so that you never use esc again

not having chord like shortcuts was one of the main reasons that led me to try vim over emacs in the beginning, so I kind of think they're "anti" vim.