What an interesting question! Many computers are an impenetrable "unibody" or otherwise glued-together cryptex these days :).

Guile/Emacs offers a way to clear a staggering amount of baggage, offering some great features, while mostly keeping add-on packages compatible. You'd think it would get more love. I use Emacs (having switch from Vim because of elisp) but I'm definitely not well positioned to do anything here :/. As it is, I'm a very strange Emacs user: no emacs-server and always '-nw' inside tmux.