Get 3 weights and use this calculator...
http://towingplanner.com/ActualWeights/TravelTrailerCatScalesWhen you weigh the truck alone the front axle weight is what you want to try to restore with the WD hitch..
So if you front axle is 3500 truck alone example then with WD engauge you want to get as close back to 3500 as you can without going over...
Next after everything is weighed compare the finished scale weights of the trucks axles with your door sticker axle weights. Don't worry about GVW of truck.
So if your door tag says your vehicle has an rear axle weight of 4000 lbs, Thats the # you don't want to be over fully loaded with WD engauged..
You may need a few passes at the scale to tune it in. It may be time consuming as you may have to tilt head back some and/or adjust chains on several passes.
Not sure how close you are now.
Post the scale weights and we can guide you better.
Last in regards to what people load in the rv is very much variable.
My camper was 4730 new with 541 lb TW.
After propane, another battery, and just my junk from the old camper I went to 740lb TW 14% and a 5300 lbs camper..
Thats 570 lbs of stuff.
Now load the food , clothes, water in the fresh tank, all forward of trailer axle somewhat I say im up into the 1000 lb range.
My camper would be up in 6000 lb weight fully loaded..
Its gvw is 7000 lbs so I have 1000 lbs to play with.
CCC is 2300 and why I bought such a large payload able trailer.
benefits also is grey and black are at rear behind axle. I can run with those tanks with stuff in them if needed.