5500lb dry will put you around 6600 wet. I would do it with my 04 F150. Should be good. As for the 30' thing. Again, not a problem. My APEX is a little OVER 30'. Follows the F150 just like it is supposed to. I have no sway at all. I do have the hitch setup correctly, as any one who tows should. I have a relaxed easy tow. It don't wiggle shake or wobble. Solid is the best word for how it tows.
Also the trucks passing doesn't jerk me around. I can feel "some" of them. But they don't move me.
As for light weight. I wouldn't consider 5500 dry light. And weight doesn't have any thing to do with quality. Mine came in 4811lb dry. GVWR of 7400. Modern manufacturing materials are making RV lighter all the time. Mine is made from AZDEL. 50% lighter than wood laminate, 50% higher insulation value, and stronger than wood laminate. The light weight material is an upgrade over heavier RVs.
Honestly. I see no reason why the TT you have chosen would give you any cause to rethink. weight really doesn't come into play while running down the road. It is mostly the front wall that holds the TV back, and hurts the MPG. If you like the TT. Go for it. As long as it is inside your weight capacities. You should have no troubles. Just take your time, and get the hitch correct. Which you would have to do with a 23' TT as well.
BTW. My last TT was 27' and 200lb heavier. Both tow pretty much the same. Both are a easy stress free tow. Both have the same effect on the MPG of the TV.