One of the main things a weight distribution hitch does is keep the weight proper on your "steering" wheels (front of your truck). Measure wheel well height of your truck, to the ground, on front and rear wheels, both with trailer connected , and without it connected. You want the distance to stay relatively the same. Too much weight on the rear of your truck will lift the front wheels off the ground, reducing steering control. Not a good thing.
If hitch height is correct , you will also be straight and level, both the truck and the trailer.
As an added benefit, most WD hitches have or improve sway control. I use Anderson, but there are may good ones out there.