I use a setup that's similar in spirit. My custom keyboard has palm keys (kind of like the https://shop.keyboard.io/), which I have mapped to control and shift (on a mac). I have a Sublime Text keymap file that has a bunch of vim-like bindings under control, so basically it is like vim but the state of my palms is the editing state, holding one down is movement, both is selection. It's really nice.

You can see the keymap here: https://github.com/trishume/SublimeTect/blob/master/Default%...