My 05 drives pretty well, but it's all relative.
The first thing to do, even with a new one is get an alignment with the RV at "travel" weight. The weight will affect the alignment geometry. Have them set caster at the higher positive end of the range, this will help with stability. You may need to see a shop that is familiar with commercial trucks. Ford may tell you that this can't be set, but it can via shims.
Be specific that you want a "before" and "after" spec sheet.
In terms of sway bars, generally on cars, you do the front first. An overly flat rear can cause worse handling (on a skid pad). But on an RV, I'd do just the opposite.. Mainly due to tail "wag" caused by semis, etc... This is just my opinion. And if you can turn a wrench, you can install a sway bar. You don't need to lift the vehicle, at least not on my 05.