I recently came across this question: Mapping symbols and special characters to home row in insert mode, which introduced me to the idea of a symbol layer on the keyboard. This seems like a nice thing to have. The post in question got bogged down in the specifics of the layout of the symbols.
The question I have is how to implement such a layer in vim/neovim?
That is, prefix key + 'a-z' results in a symbol (i.e. ( ).
I would prefer it if the prefix key was not and a relatively compact solution rather than mapping every key (if possible). My focus is currently on insert mode, however it could be useful in normal mode also, and maybe should be system wide rather than implemented in Vim.
Edit: The system I am using would be Linux/Ubuntu in this instance.