My old man has a 2002 Yukon Denali.
Holy crap it is a badass truck. SOB just goes. Also my dad beats the piss outta cars, considering, it holds up EXTREMELY well.
The 5.3 can tow a buggy, seen it. However the 6.0 (LQ4 or LQ9 powerplant) is pretty fawking awesome. Engine is stout and can easily tow heavy things. MPG sucks, ~14 mpg but hey, its a giant fawking truck.
With the new generation of vortecs, there really is no reason to go big block. Just look at the numbers and see. If you need more than 300hp and 300lb ft of torque, then you need a diesel.
Look into the denalis if you want loaded. My god they are loaded and plush. Very nice to have when on long road trips. Headed seats are awesome too. The womenfolk approve. Unfortunately the denali has AWD without a low range. Yeah, stupid but you really don't need it. I needed it once when I was on Rocky Mount at Uwharrie but other than that, never have needed a low range.
On the 6.0 engines, the throttle body and intake manifold get gummed up after ~120k. So plan on pulling them off and also replacing the intake manifold gaskets. Took me 4 hours to do...with my dad "helping". I just put the manifold gaskets on and cleaned everything else with brake cleaner. Now it doesn't idle irregularly.
The outer auto dimming mirrors go bad after 7 years. You can pick up an aftermarket one online for like, 80 bucks or something. Very easy to replace BUT MAKE SURE you stuff a rag down in the hole below the mounting point in the door. Otherwise, you'll drop a friggen nut down into the door. This is unfun.
The cabin filters need to be replaced often. Otherwise it'll mess up the HVAC and piss you off.
Unless you need a truck, the Yukon/Tahoe is probably big enough for you. I've loaded the Yukon up with 5 people and a bunch of crap and gone to the OBX for the day. Truck worked good.
The rear air shocks are leaking. Truck only has 185k on it. The little air pump is working a lot more often.
Adding a brake controller is so...very...easy. It is plug n' play. Very easy. Love it.
Speaking of brakes. The god damn brakes last forever. At 185k, STILL on original pads. Also brakes are good, very strong.
Headlights go out once every couple of years. However they are quick change-style headlamps so it is very easy to do. Takes about 45 seconds to change one of the bulbs but go ahead and have an extra pair on the shelf for when you need them. Oh, when you go buy new ones, take the old one with you. The Advance auto parts catalog isn't quite right, they keep saying it takes a 9004 bulb when it takes a 9005. Apparently they are drastically different.
GM put Goodyear Wrangler HP and Michelin Cross Terrain tires on. The Goodyears SUCK SO MUCH. The Michelins are amazing. Quiet, ride good, last a long time. The goodyears are 100% the opposite. So don't ever put the HPs on or don't buy a truck with them on.
At 185k there are noticeable items that are wearing out. Normal stuff, suspension and steering mainly. however it is only noticeable if you are looking for them.
Take it easy on the wheel studs! They can and will break! As you imagine, this sucks.
Practice changing your tire before you actually have to! GM has decided to go crazy on their tire-storing system. It'll take you a few minutes to figure it out. Rather figure it out in your driveway in broad daylight than at night on the side of I-85.
GM transmissions are actually pretty good. They seem to work well and don't explode. This is nice.
Hope this helps.
