If you plan on boondocking (dry camping - no hookups) much and need the truck to recharge the camper battery, I would recommend against changing to the 7-pin harness for two reason. The lance plug uses #8 wire for the power feed which will help recharge the battery. Using an extension and the 7-pin in the rear will add about 16' of cable which will hamper the truck from charging the camper battery. Those both combined together will reduce the charging ability by about 50% or more.
For the tie downs, unless you are very handy fabricating, definitely go with at least the fronts from Torklift. I have access to a fab shop and decided it was cheaper/better to go with Torqlift mounts. The rear are a lot easier to fabricate, but I again went with Torqlift.
2015 Ram 3500 4x4 Crew Cab SRW 6.4 Hemi LB 3.73 (12.4 hand calc avg mpg after 92,000 miles with camper)
2004 Lance 815 (prev: 2004 FW 35'; 1994 TT 30'; Tents)