Re: not good proposal: "C-z <letter>" reserved for users

[Gregory Heytings]

> Basically, I don't see a problem here that couldn't be solved much more 
> easily by updating the keybinding conventions to say that external 
> packages should not create any global bindings by default.

IMO that would be the worst possible solution, and would be an extremely 
negative signal towards third-party library developers.  Do you remember 
that Emacs is an _extensible_ editor?  See 
https://www.gnu.org/software/emacs/emacs-paper.html .

Why shouldn't an extension package for a general-purpose editor (not 
necessarily Emacs, think Atom or Sublime or...) change the user interface 
of that editor when it is installed?

> Reserving keys for external packages means that Emacs needs some way to 
> deal with conflicting external key bindings, which will inevitably 
> arise.

Yes, and this has been acknowledged from the outset.  It's a different 
problem however, these are conflicts between external packages, not 
between an external package and Emacs core or between an external package 
and users' personal bindings.  And, as you yourself say, these conflicts 
can be handled by specific functions, in a user-friendly way.  It can also 
be expected that best practices will arise by themselves, like "using as 
few keys as possible", "using a keymap on a single key if possible", "not 
using the same keys as an existing major package", "use the 4 key for 
commands in other-window and the 5 key for commands in other-frame", ...