I believe a majority of the tow rating difference between max tow Sport S and Rubicon is the weight difference between the two trucks. That's not all of it, but most of it.
Compared to the stock suspension and tires in my 2017 JKUR, I found both the Sport S and Rubicon to be "loose" with the Rubicon being a little more so than the Sport when I test drove them both last weekend. I did not check the tire pressures. The Sport S had the 3.73s.
https://www.jeepgladiatorforum.com/forum/threads/factory-trailer-brake-controller-releases-finally.21663/
More info and updates on getting it after the fact in the linked thread.
So from what I've seen and the salesman at the dealer confirmed, the auxiliary switches take the place of the media ports on the dash. Since that is where the aux port resides, am I going to be without an aux port? I have a portable Sirius radio that I move between my work truck and my Jeep...
Reach out to the sales managers at Salsbury's in Baton Rouge or Mark JCD in Lake Charles, whichever is more convenient. Their email addresses are on the respective dealer websites. They're both decent to deal with and are making deals. Community in Hammond has in stock units listed pretty low...