Nice find! Thanks.
I have some other tools for being productive from "constrained" environments.
I'm running ttyd [1] exposed trough nginx (to deal with auth and ssl) which gives me a terminal in the browser (using xtermjs). It's pretty good.
Another option I used before was shellinabox [2] (also trough nginx). Terminal emulation is not the greatest.
For GUI access i use NoVNC (exposed trough nginx) and have a systemd unit starting vncserver session.
[1] https://github.com/tsl0922/ttyd [2] https://github.com/shellinabox/shellinabox [3] https://github.com/novnc/noVNC