Thanks! So the board I tried is okay, but needs heavy JoyToKey / some other macro customization to be useful for anything else but gaming. It’s very very cheap though, and does what it says it should.
I also just found out about the [GeeekPi USB Joystick controller Board](https://wiki.52pi.com/index.php/USB_Joystick_controller_Board_SKU:_EP-0080) which provides the same functions plus six channels of analogue input. Sure, lots of JoyToKey work required on this one too, but it’s only slightly more expensive (~ $20). It also has some audio capabilities (volume/amplifier) that could have a use. The controller is much more powerful: it’s a 72 MHz ARM microcontroller.