according to the Dodge tow guide your payload is 1400 lbs and you can tow 6150 properly equipped (assuming lower axle ratio). Those are not good numbers for a trailer that will probably weigh over 6000 lbs before you drive it off the dealer lot.
Strictly speaking, most people run out of CCC before they hit Max trailer tow weight. you might actually be the opposite. that 4.7 is killing your tow rating, the 5.9 adds another 1K pounds and might be the difference in the trailer you are looking at.
Note that electric brakes and WDH do not diminish the weight you will pull, but rather allow you to pull up to, but not more than, your trucks rated ability. Without those, your abilities would significantly decreased.
2013 Coachmen Freedom Express 320BHDS pulled by a 2005 F250 King Ranch CC
A rainy day camping is better than a sunny day at work.