I had a PS1/PS2 controller via adapter for many years before controllers got good again on the PC. Did have a USB adapter for my xbox controller but mostly used that to have a USB port on my original xbox and was the 360.
Nowadays been toying with a wii nunchuck to replace the keyboard for movement in games, and a mouse for aiming.
I might have to try a gyro mouse out as I had missed that and it seems a few do decent range as well. That said I might have to make the first "too much like work" comment in my life as it would be too much like CAD mice/movement tools
https://www.3dconnexion.co.uk/products/spacemouse.html , though in this case it is more that I would not want to unlearn anything I have for CAD.
That said some of the video editor input devices with nice jog controls could make for an interesting game input.
I did use my drawing tablet for a few games once. Did not spend any real time honing either the relative or screen mapped modes, or sensitivity for the former though.
"unless it's a game that doesn't let me separate mouse and right analog controls"
They make programs for that you know. Many those joypad to key programs cut the other way and allow you to present whatever form of controls as whatever you like and dodge issues with games not programmed well when it comes to input options. That said it is also those games which cause me most trouble with more unconventional setups either for lack of helpers or the helpers getting in the way (autoaim with a mouse often sees me move away from a head I am about to click on).
The next big step is games which decouple look and weapons, so few do and those which go there are often instant motion sickness for other people (even the halfway house of head bob and the three quarter house of taking account of jogs in the ground does a lot of people in).
