headroom? I have a touring and test drove a model without the moonroof. The headroom is the same or potentially increased with the fabric cover rolled back. You don't lose headroom by having a moonroof.
For the panoramic you DO seem to lose the ability to choose the middle-row seat being a bench (seating 3), and you can get it seating only 2.
For what it is worth, this is my first vehicle with ventilated seats, and my first with the rear-view camera built into the mirror. I absolutely love both features. My 2nd day with the Ascent we drove 19.5 hours south, with 5 people, and luggage blocking the rear view mirror. I flipped on the camera and smiled the whole trip. It has a nice wide view that complements the mirrors and the blind-spot-indicators beautifully. I found it odd at first that I could turn around and see my kids, but not see out the back, then would look up in the "mirror" and see out the back fine. I got used to that really fast. A few times I have leaned up to check something on my face, only to remember that it is not in fact a mirror when my face did not appear.
But ventilated seats. Oh lawdy-lawdy-lawdy, where have they been all my life? I can start the Ascent from my phone and go out and plop down on a cool seat in a cool car (on our trip to Florida) or now back at home in the northeast I can go out and get in a warm car with warm seat (alas, you cannot activate the steering wheel heater from remote).