Love my Suburban! There is plenty of room for my family of 7 and a TON of cargo space for all our "stuff"! We had a Yukon Denali before that and I also loved it. We had plenty of room for seating, but not enough cargo space-which is why we got the Suburban. I think if you really want room for your "stuff", you should go with a Yukon XL or Suburban.
We just bought our Suburban in November and we also looked at minivans (ughh). I will admit that there are some nice conveniences, like the sliding doors and other kid friendly features, but honestly, we have more room in the Suburban. The kids have larger seats and more leg room, which makes for a much more comfortable drive. There is also significantly more cargo space in the Suburban. The biggest pro to me about the big, gas guzzling SUV's is the safety. I feel so much more confident driving my precious cargo knowing how much steel and bulk is around my children when we're on the road- to me, that is priceless.
Added- we also had a Pilot before our Yukon Denali and that was a great car as well. The car itself was smaller than the Yukon, but we actually had more cargo space in it. When the third row was down, it was flush with the floor, instead of the seats stacking, like with the Yukon.
Also, if it comes down to either a Yukon Denali vs. a lower trim level Yukon, Tahoe or Suburban, the gas mileage isn't terribly significant. I thought since we were going to a smaller engine (from the Denali to the Suburban) that I would see a significant change in mpg-but I really haven't. In our Denali, we got around 11-12 around town and the best we ever got on the highway was 17. With my Suburban, I usually get right around 14 in town and 19ish on the highway. To me, that is not a huge difference. So, if it comes down to it (and the money isn't a large factor) I would definitely go with the Denali. I do miss the power of my Yukon!