I use JOE in its "emacs-ish keybindings" mode (which you get if you run it as 'jmacs') for small "just run an editor in a terminal to edit this config file" jobs. I wanted an editor which was fast to start up, terminal-based, and emacs-like, and this was the one I found 20 years ago. It's always been reliable and it's always been available as a Debian package, so I've never felt a need to look for something else.

For long running edit sessions I use real emacs; I know you can set that up in a client-server arrangement to avoid the startup speed problem, but I never had the effort to investigate that; besides, sometimes you want to edit a file as root, who won't have a long-running emacs.