The worst thing you can do is speed up.
Looking at your numbers the hitch is pretty close, but might use a little more to get some of that 180# off the steer axles transferred to the trailer and rear wheels.
The best thing you can do is get a "heftier" TV. I understand that you have upgraded a great number of components from a 1/2 Ton to a 3/4-1T platform but the frame and drivetrain are still 1/2T (this includes the steering components). A steering stabilizer may help, but what would really help with a TT that weights more 9300# is a vehicle that is designed from the frame up to pull almost 5-tons.
All other "fixes" are just temporary bandaids for the real issue - not enough TV. You are experiencing the white-knuckle driving associated with too much TT for your TV.
And please, please...DO NOT SPEED UP as your solution. For the sake of you and all those on the road with you.