When I get blown by the trucks, I don't feel like I'm going to run off the road or lose control. It's one of those things that even though I know it's going to happen, it's still surprising every time.
In terms of getting a bigger tow vehicle, unless I move to a dually, there's not many vehicles that are "bigger/heavier" than a Suburban. But, find me a Chevy dually from the 80s that's not utterly destroyed or going for a fortune and I'll buy it.
While Chevrolet refuses to rate my Suburban for more than 2000 pounds because it didn't come with the towing package from the factory, the official GM literature for my year Suburban states that my engine/transmission/gear ratio combo is good for a 9500lb trailer and 16,000 GCVWR. A Suburban in any form is obviously capable of towing more than a 5x7 trailer of clothes.
Since I live in my trailer, it's always got a full load of food, clothes, water, propane, etc. I also accept that since I'm a full-timer, I'm darn near overweight on the GVWR of the trailer.
In terms of speed, I've been working my way up. The first time I towed the trailer with an inadequate WDH with no sway control, I could barely get above 45 before the trailer started swaying on me. With the Strait-Line and proper weight bars and sway control, I was able to do 55-60. I'd do 60-65 all the time once I get more confident in this bow wave issue.
I do appreciate everyone's comments and guidance.