Good Report dog. Most of your bad and ugly evolve around being the first kid on the block to get that new shiny toy. Being the first also means being the guinea pig.
As much as I drooled at the 2020 models and the 10 speed trannies I did not want to be the first to actually use and test these new features. I settled on a 2019 that I am very happy with. My 2019 lacks the 10 speed tranny but still has more power, better braking,modern electronics and more ability than my prior pre emissions 07 Duramax dually. I'm sure your 2020 takes 2019 to another level but it is a first model year which means things need to e sorted out.
I have learned not only do the trusting consumers not know how it's all designed to work, but the dealerships often don't know what's going on either!
As you learned from your bag of parts it takes times for these new features to be fully understood and actually put to real life use.
I have kind of resolved myself to buying the last run of a vehicle platform vs. the first run of the platform.
The last year all the kinks have been worked out and the platform has been optimized. With first year roll outs the kinks are just being discovered!
Hearing that some of the new camera features will not work with a fifth wheel is disheartening.
Hang in there it seems that you are overall satisfied with your new beast. In time those kinks will get worked out and conveyed to the dealerships. Unfortunately the learning curve just takes time.
In the meantime enjoy that drivetrain and smooth power the gadgets will sort themselves out in time.
19'Duramax w/hips, 2022 Alliance Paradigm 390MP >BD3,r,22" Blackstone
r,RV760 w/BC20,Glow Steps, Enduraplas25,Pedego
BakFlip,RVLock,Prog.50A surge ,Hughes autoformer
Porta Bote 8.0 Nissan, Sailun S637