I'm late to the thread, but this was me a little over a year ago. At the time I pulled a 33' 7,600lb travel trailer (Transcend Xplor 265BH) with a 2018 Expedition Max Limited. The towing experience was ok, but I had a good amount of truck suck and felt uneasy in crosswinds. I also had a ton of issues with the Expy (cam phasers x2, both turbos, 7 leaky shocks, and more), so I started looking at the Yukon XL Denali. I rented one on Turo and pulled our camper (Denali but without air suspension). It was noticeably more stable towing even though Yukon had lower tow ratings. So I decided to order one and got a 2023 Yukon XL Denali Reserve. I've now had it for a year and put 24k miles on it.
I agree with your likes and dislikes list. I will say that I get lower fuel economy (about 2mpg) on the 6.2L V8 than I did on the EcoBoost. The seats are firmer in the Yukon and the Bose stereo isn't nearly as good as the B&O IMO. The other things I preferred on the Expy were the visibility over the hood, the tilt-and-slide seats, and that the third row seats had latch anchors and a headrest for the middle seat. I prefer everything else on the Yukon. I haven't needed any repairs yet, the fit and finish are better, it tows better, it has features like air suspension and head-up display, and the transmission stays much cooler. I'm very glad I made the switch.
For towing, the 6.2L has ample power. It has to rev more to get power compared to the EcoBoost, but it's never lacked power going up steep passes in the Appalachians. It also sounds great when it's under load. When towing I get close to the same fuel economy as the EcoBoost. I have the air suspension and it tows great. It's always level and I don't get much porpoising. I didn't have any complaints when I tried towing with the non-air Yukon either, but that was so long ago I can't remember how they compare. But I'm glad I got the air suspension and would do it again.
The transmission in the Yukon runs significantly cooler than in the Expy. Around town I'm seeing 145-165 degrees depending on traffic. The Expy used to be around 210 degrees. I haven't towed our trailer up slow, steep passes with the Yukon yet, but I did with the Expy and it got warm. I fully expect the Yukon to do better in the same scenario based on how much cooler it stays when towing at speed.
We recently downsized our travel trailer to a 28' Airstream. Towing that my transmission temps stay pretty low on the highway (150s-160s typically) and I get significantly better fuel economy (11.5mpg vs 8.5mpg with our last trailer). Payload on my XL Denali Reserve is 1,427lb. I've taken some steps to lighten the tongue weight of the Airstream and stay under all the weight capacities of the Yukon. We're close to the limit, but it really tows well. My wife really didn't want to get a truck and lose the third row seats, so this was our solution and it's worked out great so far.