A few Werks ago, I sold my Xbox one and with that my only working controller for my PC. Since then, i have been playing hollowknight and Jedi fallen order on my old Xbox 360 controller with its unlikeable d-pad, even after multiple mods to it.
And with the steam controller coming, im eagerly awaiting the steam controller
My guess is about 100-150€, since the price of a General controller with back buttons and no Hall effect Joysticks or touchpads is already about 100€, so this + all the cool shit steam is doing will be more.
Yes, but you can use any input device with steam, unlike the consoles where you need a controller thats partnered with the brand.