I've used KDE on my convertible during uni and it worked pretty good. I mean for a GUI oriented setup your options are pretty much KDE, gnome, cinnamon, xfce (don't know how good that is with touch though) or cosmic (is that out yet? Idk tbh).
Afaik gnome and kde both have good touchscreen support, maybe you'll need to do some slight modifications, so I'd say just try them out and see what you like.