Halt Ton Towing

I am really not an expert on 5th wheels but that 10,000 lb tow rating is not having a 5th wheel hitch in the bed of the truck and the 1600 lbs it will have hooked to it. Loaded weight and actual weight are two different things. Stopping and down hill are another thing altogether. Wishing you luck.

The thing that you need to remember is what YOUR rig is designed to tow.
Do not rely on dry weight because it can be deceptive. Particularly if you are at or close to your max. weight. The weight you need to be concerned about is the GCVWR (Gross Combined Vehicle Weight Rating) of your TV. If you are within 80% of that max., you are approaching problems.
You will read lots of posts on this forum about how well their rig tows when overloaded. Don't be swayed. Their rig will wear out faster, break down sooner and become unpleasurable to drive sooner than if you have an adequate tow vehicle.
It sounds like you are trying to justify towing with an inadequate rig by citing all of the "extras" and safety things you do. Here is the issue: If you are overloaded or close to your max., and you have a panic stop (an unanticipated emergency 'slam on the brakes' stop), you more than likely will find brake fade or failure. You can't plan for that type of stop. You can plan for minimizing the effects by towing within the rating on the tow vehicle.
Not only that, but you will spend a lot less money in the long run if you start out with an adequate tow vehicle.
I expect to be trashed for saying this, but I have been there-done that with an inadequate TV. When I upgraded to a vehicle designed to tow more than what I was, I never had trouble or expensive repairs.

Sounds like you've thought it all through. The only thing I'd add is that you visit the scale and verify all the applicable weights to make sure your calculations and assumptions are correct.