I fell for the meme and ended up getting a trackball, only to find out it's actually really good. I'm heavily left-handed so "ergonomic" stuff usually just isn't available/useful for me. I got the Kensington Expert. People write it's poorly manufactured (for the price) and the tracking sensor isn't up-to-date. The poorly manufactured part I can't confirm, the tracking sensor maybe but I mostly think it's a skill issue because you get used to it. It's really fun to use and resolved all my long-computer session left-hand wrist issues that were cropping up in the last few months here and there. The pricing might be a turn-off but I really like this device. I also used to think trackballs were obsolete and a joke.
In linux, layout/button programming usually shouldn't matter because at least with X, you can freely program however the computer interprets what comes from input devices with onboard tools. e.g. my capslock key is my ctrl key when I hold it and my ESC key when I just tap it. All with X onboard tools. I recently switched to 60% keyboards I really like but which have no arrow keys. In the terminal and with editors, it is not a problem for me since I usually used either wordstar-esque or emacs keybindings. Sadly, outside of the terminal this is often not really supported (e.g. in the browser in the editing window for writing posts here) and I had to deal with inconsistent input keybindings and programs that often are way too reliant on arrow keys these keyboards don't have and are only to reach via function key combination.
The linux kernel also has the uinput feature, which basically allows you to create virtual HIDs easily that plug directly into the kernel. I wrote a small shim that blocks and redirects all keyboard input from my physical keyboard through such a virtual keyboard. Since the virtual keyboard is purely software, it can query the X server which window is currently focused and interpret keystrokes in different ways through a program-dependant keyboard map I can customize, so I can basically remap my keyboard per application and even have special keyboard modes, e.g. a keyboard combination I can press switches all input to the same shim running on my notebook via SSH tunnel, basically acting as a software KVM switch that only needs the linux kernel and ssh and is completely display-server agnostic. (contrary to things like x2go that need the X server)
tl;dr: if you run linux - as long as your input device is HID compliant - you do not need a driver for anything.