Technically a fifth wheel doesn't apply tongue weight as the pin is located slightly forward of the rear axle. Tongue weight is any weight applied behind the rear axle.
Fivers and goosenecks inherently tow better that a bumper pull as the pivot point is the rear axle and the weight distribution to the front axle. Bumper pull trailers use the rear axle as a fulcrum of leverage to push the front of the vehicle around (up/down and side to side). That why using a WDH and how you load the trailer is important with a bumper pull.
Several trailer manufacturers make 1/2 ton truck weight friendly fifth wheel trailers. The brakes on an EcoDiesel are the same as on the Hemi which has upwards of a 10K lbs tow rating, between the trailer brakes and the truck brakes there is enough there to to stop that much. Keep in mind at 10K lbs of trailer you've added about 150% of total weight your trying to stop, distance to stop gets a whole lot longer.