My previous game system was a Wii U which I homebrewed. Also had a Wii many years ago. I'm considering a Switch to play TOTK (completed botw on Wii U) and Just Dance for my girlfriend. What should I take into account when picking a system?

I'm kind of lost in all the variants and shit. Is OLED the only current model? Do they vary in performance or merely the screen type? Are second-hand devices which come with digital games locked to the original user account? Is it risky to buy second-hand? Can game cartridges be moved between systems and sold freely? Is the joystick drift still a thing? Is homebrewing a thing? Do cartridges carry save files like in NDS? Are digital releases generally cheaper than physical? Does it accept any usb type c charger? Does it work with usb type c hubs with hdmi output or does it require the docking station? Is online play (in mario kart for example) still free to access like it was on Wii and Wii U or did they move to subscription system?