The screen is so bright it makes my room look dark!! News update here, a friend gave me their old tablet display monitor (Huion GT220 v1 not v2) and I installed it today.
I haven't figured out yet how to use both monitors without mirroring (when I turn mirroring off, it causes the calibration to be way off). This was an issue with the XP-PEN too but only because I'm using not even Ubuntu but Manjaro.
EDIT: I used xrandr and xinput to fix everything up so it's all good now!!












