ergoemacs-mode VS persp-projectile

It's a tiny tweak that gives something like 1% of the functionality.

The real, useful, working CUA mode for Emacs is here:

https://ergoemacs.github.io/

If you start with framework you might not learn enough to solve problems later, but using it later to simplify your config should be ok. For example ergoemacs http://ergoemacs.github.io/ is a nice way to make Emacs more ergonomic and easier to use(if having problems with default configuration).

For example I use https://github.com/ergoemacs/ergoemacs-mode, with some commands that I have acquired as muscle memory from using Emacs/mg for long. And still I use nano when I need to do small edits to a file. I also do it almost without thinking about it, especially when doing "sudo nano whatever". Mg should be better for me, but nano is engraved into my palms for some reason.

That documentation seems very outdated. The changelog is from 2013 and that function was removed (according to an issue) before 2015.

Xah Lee and friends maintains a mode called ErgoEmacs that implements most of the changes he proposed: https://github.com/ergoemacs/ergoemacs-mode

I am currently trying with perspective rather than persp-mode, as it segregates the buffer list as I like (#1 above). I've got projectile with persp-projectile, and that seems to give me what I need for project navigation (#2 probably, still not 100%). I get some help in my mode line for project focus (#3, partially).

Aye. I often have two interdependent projects I work on simultaneously, and I use a lot of persp-projectile (https://github.com/bbatsov/persp-projectile). I would love to try project.el but sadly it seems like it doesn't integrate with perspective.el yet.

I also use purely emacs for "commercial programming" (as you refer to it) and for managing multiple projects I use projectile + perspective + persp-projectile.

I had my own rolled version of this in my config until recently when I swapped to perspective and perspective-projectile.