You really need to drive each vehicle. The Sequoia is bigger than it looks and feels cheap inside compared to the LC. The LC feels cheap inside compared to the Caddie. Also consider if you plan on towing anything significant in size - The GM pulls with more power.
That being said, I have colleagues that have the Caddie and and Tahoes. The Caddie is actually a stiffer, rougher ride than my LC. I was surprised by this, but I think it is the low profile tires transmitting road conditions and firmer seats. There was also the problem with the variable valve system, where the truck would run on 4 cylinders when accelerating around town and then run on all 8 on the highway (completely reversed program).
Nothing beats getting in each vehicle and trying them out. When I was doing what you are doing, I found that the LC was jus the right size, between the Tahoe/Sequoia and 4Runner, as well as having very high quality fit and finish. All vehicles are expensive to fix these days. Mine has 126,000 miles on it right now and I still put around $2k into it this year for tires, brakes, bearings, timing belt, etc.
Good luck.