Only upgrade I did from my old kindle paper white was to a water-sealed version. Really nice to take it to the beach or a pool then just hose it off when I’m done so it doesn’t have sand and such everywhere. Just less stressful to carry around in general.

USB-C on the newer Paperwhites (and base Kindles? IDK if those changed over yet), in case you just want all your (portable) gear to be USB-C.

What is extremely annoying is people constantly and universally lauding the Kindle for Kids option, when it is only offered in the US. Or, at least, its barely offered in the EU.

I gave up on my first paperwhite last year (10+ years old). Would randomly lose its charge, which was annoying when bringing it on trips (and often not having an old micro-usb charger lying around). And from being stuck into all kinds of pockets and bags without a protector (half the use was it fitting in my pants) had seriously scratched up the screen. The new one I got is nice, but other than the old one being beaten up, I don't notice much difference. A bit faster to click around, but in the end it's mostly the same.

Not sure what my old kindle version was, it had a keyboard though, but I upgraded eventually because I wanted a warm toned backlight. It's nice that the newer ones are a bit snappier too.

I upgraded from Kindle Keyboard to Kindle 2023 last year. Backlight is very nice and I appreciate its lighter weight, but otherwise it's pretty much the same.