And what you’re describing that you’re experiencing isn’t “trailer sway” in the true sense of the definition. Although a little more tongue weight would help.
I couldnt imagine installing sway control on a little ole trailer like that being towed with a vehicle that large and capable compared to the size of the trailer.
First question is ask yourself what your basis for comparison is. IE how much towing experience you have or don’t have. Semis and cross winds push cars and light trucks with trailers around. Whether what you’re experiencing is excessive or normal is subjective.
But the tongue is a bit light. Is it better with no water? Try some extra weight forward to increase the tongue weight. However you can effect that.
2016 Ram 2500, MotorOps.ca EFIlive tuned, 5” turbo back, 6" lift on 37s
2017 Heartland Torque T29 - Sold.
Couple of Arctic Fox TCs - Sold