Not exactly a solution for your issue, however....
I agree with you about the thumb joystick. I did this... thing.... using a broken PS2 controller, an empty shell that come from a bunch of WII accessories, the cable of a broken joystick and some (rather awful) 3D print. I just added a couple of diodes in order to separate the joystick potentiometers channels. It works as an Atari controller.
