Congratulations! I'm jealous!
With that small trailer is possible that you might be able to get away without a WD hitch. The trick is to find out how much weight the tongue takes off the front of the truck. GM says in the manual that when using a WDH to adjust it so that the front fender is brought back to stock height.
So, without the trailer on, measure the fender height at the center of the wheel hub to the fender lip. Then put the trailer on but do not put the WD bars on. then measure the fenders again. If they rise more than 1/4" then you need to use the WDH.
The reason for all this is steering control. Even a 1/2" rise can make the steering feel "squirrelly". Also, don't worry about rear squat. 1 to 1 1/2 inches of squat is normal.