The OP wrote, "We're still looking at getting a Winnebago Micro Mini 1700BH TT, which is single-axle, 20'9" overall length, 3000 dry/3800 GVWR."
Wow! To tow that monster, you need at least a one ton dually with a Hensely hitch. Got to be safe, you know. NOT.
You are correct in looking at all the numbers but unless you are going to haul a thousand pounds of junk in the bed of the pickup, you will have plenty of capacity. If you have even the slightest tendency to sway, there is something wrong. A fancy hitch might hide the problem but it is easier and just as correct to set up the trailer right in the first place. It should not sway, regardless of the hitch involved. My trailers do not sway.
