What is joystick mode then supposed to be that you can activate in the settings?
By gamepad I am referring to my PS3 controller, btw.
If you want to separate movement from the direction the player is pointing at (like you can retreat walking backwards while still firing at the enemies) this could be done by one analog stick for movement and the other one for direction. Firing would be best than on one of the shoulder buttons so one can keep moving with both thumbs...
I don't think the new InputSystem would be required for doing that, at all...