Monaco Knight handling issues

I have a 2003 Safari Cheetah with 45,000 miles on it. I tow a Nissan XTerra which weighs 4,500lbs. My chassis and suspension is identical to your coach. I changed over to Koni shocks a couple of years ago and it made a big difference in eliminating the "Porpoising" problems. I have never had the drift issues you speak of. I can take my hands off the wheel at 55 t0 65 MPH and the coach does not drift at all except for the crown on some hyways. The wind does effect all RVs no matter the size and the weight. Your toad shouldn't be effecting the stability of the coach if your towing set up is correct and if your toad isn't grossly out of alignment. I would suggest you take the coach out on a good road by itself on a no wind day and see if you are still having the problem. If you do then I would look at front tire balance and alignment. You shouldn't have to be fighting the steering wheel.