While the DS4 is my second favorite gamepad, I tend to find it inadequate a lot because of it lacking the extra back buttons and the ability to easily make use of gyro and many hotkeys at once. On a Steam controller, I usually set a virtual 9 button numpad when you click the right pad (it's normally mouse movement), which is easily relatable to a normal hotkey bar UI, and every modifier multiplies the buttons from there. So all the important hotkeys can be used while gyro allows camera movement at the same time. Although that's not nearly the limit of Steam input, which could also use "sub-modifers" (double press, long press, etc) to multiply the amount of keybindings further.
I personally think the Steam controller without Consoleport can meet or exceed what a normal controller can do with it. In terms of raw performance in higher level content. I could only compare myself to other healers using Consoleport though, because I've only ever mained a healer since I started WoW. Do you have any logs or anything from anyone healing raids with a normal controller?