Don't know where the "KC, sweet sauce" thing came from, though sweet sauces are usually available for those who like them. I suspect KC Masterpiece had a big bearing, and it is not representative of KC sauces. It was invented by a doctor to appeal to the masses.
Drop by KC sometime and we will visit Arthur Bryant's, Gate's, Fiorella's Jack Stack, Wyandotte County BBQ, Hayward's, Quick's, BB's Lawnside, LC's, Rosedale BBQ, the list of fine Q places goes on & on. You WILL have a different take on the sauces. And you WILL smell smoke at all of them. Won't see any of them at competitions though.
Gotta say I have had everything you listed and like all of them, each is different and has it's merits. I've been around a bit and my hands-down favorite is Arthur Bryant's on Brooklyn in KC. And the sauce ain't sweet. Another favorite is Rosedale BBQ on Southwest Blvd. And the sauce ain't sweet, has heat. Another old favorite is Crosstown BBQ in Springfield, MO, 2 hours south of KC. And the sauce ain't sweet.
But the Q is fine.