Wow lol. I just posted the exact same comment, there are dozens of us! I literally cannot play rocket league without the steam controller for this reason.

Also set rotate left and right to the grip triggers (roll in aviation terms I guess).

You can set a dual-stage trigger in Steam Input binding with any controller its trigger range, its not something unique to the Steam Controller.

Sure, but having a tactile bump in the travel makes it that much easier. I can see the argument that it might seem overcomplicated or confusing to typical users though.

If we get really lucky, some gamer dev will look at the Sony DualSense driver (yes, they wrote and upstreamed an official one) and figure out a way on how to shim / expose the adaptive triggers to Steam Input bindings.

I wonder if the haptics are programmable enough to simulate that.

Steamdeck has the dual stage triggers right? (Though maybe just in software?) I'd be shocked if the new controller is less capable than that.

Hoping it's there just not mentioned.

This controller seems more like it's going for parity with the Deck, which doesn't have dual stage triggers. I wouldn't get your hopes up.