I played through Doom Eternal like that on my Steam Controller where I mapped mouse to the touchpad for quick turns, gyro activated on touch, and mapped some of the weapons on the touchpad so I could swap to them when I clicked by setting up a dpad modeshift on right pad click with an inverted outer ring for center click.
Turned off aim assist and went my way.
My hope after seeing that the joysticks themselves look like they can be removed from the main board is that the touchpads can be relocated to the top without too much hassle and put into a 3D printed top shell made by the community. So if that were possible what I’d probably do is pop off the XYAB, dpad, and board holding the joystick so the touchpad can be moved up to make the touchpads comfortable for primary use.
And then I’d rely on the back buttons and set up a dpad modeshift on a right pad click to enable edge and center clicks, so I wouldn’t miss the absence of the other inputs too much. I also use touchpad for movement where I’ll often set outer ring to sprint and map crouch/slide/dash on touchpad click, so cuts down on needed inputs further.
So that’s my hope that modifying the new Steam Controller for touchpad users will be as simple as 3d printing a shell and opening the controller and not require further things like soldering.