I think you're on the money with the options choices, the only thing I would change is substituting a Ram 3500 for the F-350 :B :B :B
I would stick with the 4x4, granted we don't use ours much either but when you need it, you need it. I got the CC/LB and it is one long truck. If it was a dually it would really be a beast. I agree with you that for hauling a camper, the XC/LB combo is better than the CC/SB for the reasons you mentioned.
I would also spring for the 5er prep, having the 7-pin in the bed means you can plug the camper in there and have the one on the hitch available for whatever you're towing.
I'm surprised the that they will even order it for you, the chip shortage has pinched production so much that dealers can't even get lot inventory. Somebody posted over in tow vehicles the other day that their local dealer wants $5k over sticker on anything new, no negotiation.