I also have a family of 5. My kids are younger than yours. I had a 2015 Jeep Wrangler Unlimited. Even with three car seats stretched across the back seat, the experience was not bad at all. Although young, my children never complained.I’m not surprised at all. Just wish it worked out better for a family of 5.
I only sold it (to my dad so it stayed in the family) because it grossly lagged behind current safety technology; mine didn't even have side airbags. I became concerned that my selfish desire for top-down cruising in my 4x4 was doing so at an unfair compromise to my family's safety. Ultimately, I decided to move on to a full-size truck.
I will say the crew cab Sierra (I know you don't like GM, but my experience has been great) is much roomier than the jeep. We would consider taking the truck on a longer trip or on vacation if we so desired. It has the latch system we wanted, airbags, and a host of computer-assisted safety doodads (which I never cared about until I made these three chuckleheads.)
I love the truck, but when I saw the Bronco in its reveal form and looked at the safety suite availability, I'm thinking that this vehicle can give me the best of both worlds, safety, and my families coveted top-down rides.
Yes, it will be smaller than the full-size crew-cab truck. Yes, it will negate that vehicles use for vacation or long trip traveling. But for me, the around town top-down drives with my wife and kids make up for the sacrifice in space. I have experienced both and the space issues take a back seat to the smiles.
The wife is happy driving a larger SUV.