Earlier quoted context omitted.
It uses gnuplot I think as its frontend. Gnuplot is quite powerful if you understand it and can trick it correctly. Regarding the interface being ugly it kinda also depends on which graphical frontend gnuplot is using, there are multiple. I like the Qt one.
nothing beats emacs & maxima-mode https://community.linuxmint.com/img/screenshots/maxima-emacs...
I was going to try again before commenting, but I broke my WSL setup last week and didn't have time to fix it yet, but I sure will try it again next month.