I use KDE Neon on my laptop and I’d prefer to have KDE as a DE on this one too (if possible) but I don’t mind a non Ubuntu base. Basically I’d just like to be able to play games on it without much hassle but I know how to paste commands into the terminal if the need arises.
The bazzite project website has an explicit “how-to” for extra drives. Worked for me with no issues, though I am definitely more experienced with tinkering with that kind of thing.
Wish I’d known this a month ago xD.