I think we are talking the same thing on the upfitter switches. I have them now. They are mounted low on the dashboard. For maybe $200, if I don't ever use them, it's no big deal.
The diesel and transmission....without going back to the Ram site, from memory, if I go Cummins+Aisin I get maybe 130 more ft. lbs. of torque (930 ft. lbs.?) and maybe 50 more HP than the Ram automatic. It's expensive at about $2800. I haven't seen any different HP/torque values listed for different rear end ratios.
The alternators...Think I'll go with just 1 but higher output.
Rear axle...the 3.42 has served me well, but maybe leaning to 3.73. Mostly to maybe avoid locking out 6th gear.
The weight...I told my previous owner that I wouldn't buy it until we ran it over a CAT scale. I could tell he wasn't very receptive to that. He just pointed out what Bigfoot said on the rear label and the paper label in the wardrobe. I think the rear tag said 2820# and the paper label maybe 3280#. It took forever to load it on my truck...very unlevel pad and he had never loaded it before! A storm was brewing, and too much help from the neighbor. Anyway...I didn't weigh it until after I paid for it. With full fresh water, 2 changes of clothes, minimal food, a very few tools, it came to 3880#. My payload is 4018#. I've used it loaded very light for a couple fishing trips. This last trip was packed for 6-10 days, heavy clothes, lots of food, etc. I was over RAWR, payload, and right at the tires limits. So it gets down to...do I want to keep this thing or get rid of it? Keep it. Bite the bullet and go get a bigger truck.