I managed to get Midnight Commander and Vim working as a snappy package in a classic confinement… kind of. I am having issues with what may appear to be with config files. Midnight Commander starts with an error saying, “Error: Unable to load ‘default’ skin. Default skin has been loaded”, and it loads with a very basic theme. I realise the ~/snap/mc folder is empty, same with Vim’s folder. So, I won’t be able to configure it. It can’t be changed system wide either as /snap is read only. Vim works, but it functions like old Vi, such as the notification that tells what mode you are in does not appear.
You’ll probably want to set VIM and HOME accordingly. I snapped nvim (though it’s not classic since it wasn’t a thing yet at the time) so you can compare notes.