Huh. I use Vim a lot, but almost never use Esc. Ctrl+C exits insert mode, and for shortcuts the meta key is so much more convenient.
Anyway, from the sound of it it's more of a power user key, so people who make frequent use of it will be able to remap either the keyboard or the application to suit their own fancies.
I haven't decided yet if I'll do custom Vim bindings, or if I'll just use Nano. I found that on my mobile phone, the keypresses I saved by using Vim didn't quite make up for the increased number of keypresses required to type special keys. That was with just 20 input keys, though, so some experimentation seems in order.