As I casually shop around for an eventual replacement for my Suburban I'm running into the same issue of cab length vs. bed length.
Can't understand why the manufacturers have settled on the 5.5' bed size as the "standard" CCSB for half ton trucks. 5.5' seems to be a very strange choice. Why not 6'? Compact trucks have had 6' beds for decades, and even in "the old days" when you only had "short bed" and "long bed" trucks, short beds were either 6' or 6.5'.
The 6.5' beds just seem too long in a crew cab truck. And the "half cab" trucks (GM Double Cab, Ram Quad Cab and Ford Super Cab) seem too small to have back seats that are actually comfortable for adults to sit in.
It annoys me that GM decided to dump the Avalanche in 2013 since it was IMO an ingenious way to square that circle: With the disappearing mid-gate, It could have either a usable 8' bed OR the ability to carry 5 ADULT passengers, and all in a package that is actually smaller than a modern CCSB half ton! But GM killed it so they could focus on the cheaper Silverado.
My dilemma comes down to whether I want "Short bed/Long cab", "Long bed/Short cab" or "long bed/long cab." The latter, IMO, is the least attractive to me.
One could propose a simple analysis which would be "which do I do more often: Carry passengers in the back seat, or sleep in the vehicle?" If it's passengers, that suggests long cab/short bed. If it's sleeping, that suggests short cab/long bed.
The truth is, I rarely carry adult passengers in the back seat AND I haven't slept in the back of a truck since 2014. So really, by that analysis, either configuration would work for me.
If I'm being honest with myself, the potential ability to carry passengers in comfort and safety probably outweighs the very limited likelihood that I'll sleep in the back. At 6'1" I could - barely - sleep in the back of my '04 Tacoma. A sleeping platform in a 5.5' bed MIGHT allow me to sleep at a diagonal. Probably not super comfortable but eh, I've slept in worse conditions (once I spent 2 weeks sleeping the front seat of an M151 Jeep, leaned up against the machine gun post. Granted, I was a LOT younger, but it can be done if you're tired enough and the ground is muddy enough.)