Thats pretty nifty! Idk how old that tablet is, but if it starts getting up there in age, I'd pay attention to the battery health. Eventually you might need to swap out the battery if it gets too old or it might swell, esp if its gonna live plugged into the wall. That happened to my parents using an old android phone as a security camera after a few years.
Cheapshark is what I generally use. I haven't bought stuff from every seller they track, but so far I havent had any issues with Humble, Greenman, GoG Fanatical, Gamebillet, or WinGameStore. Tho for the last two I've only made one purchase through them. Take it as you will.
Blender: If you're interested in 3D modeling or Animation
Inkscape: If you have any need for a vector graphics program thats a bit like Adobe Illustrator
OBS: If you need to do any screen recording or livestreaming
Haruna Video Player: It plays videos and can also play youtube videos if you paste in a link. (This also pulls in yt-dlp as a dependency, which allows you to download youtube videos and the like from a terminal)
btop: A nice looking system resource monitor that runs in a terminal
for a bit more context, ncdu is a Disk Usage analyzer that runs in the terminal. If you've ever used WizTree on windows, its kinda like that. Really useful to see whats taking up space on your disk
Im sure people will still be using Java 8 then, so its fine