I kinda really love, and kinda dislike my Steam Controller. I agree that it is excellent for the couch browsing experience. The touch pad thing works great, and I also enable the gyro controls highly dampened and on extremely low sensitivity to aid in pointer aiming. Flick around the big touch pad with a thumb, then touch the other pad and wobble the whole controller a little bit to fine-tune where the cursor is. It works great!
The paddles are a good idea with poor execution on this controller, they just never felt good to use. The buttons feel unsatisfying to press. Overall I still like it, and I think it is a shame they discontinued it.
It is a crime that nobody suggested Celeste as an action game protagonist.