My best advice on your TV, If you have P-rated tires air them up to near max pressure indicated on the tire itself ( I think mine was 45 PSI so I went to about 43) and tow a bit with it first, much cheaper for Air than the RAS. I had a 2013 F150 SCREW Lariat with Maxtow with both the tire experience and RAS, so very similar
The air pressure in the tires was the biggest difference I noticed, the RAS was the second biggest. I actually did the RAS before I did the tires, wish I had done the reverse in hindsight. I still don't regret the RAS however, it was the difference between the wife and kids wanting to ride in a different vehicle vs not.
If you find the PSI makes a big difference, next time you change tires, look at LT rated tires which have much stronger sidewalls. The P rated tires the sidewalls flex, gives it a little left-right wobble in the back end is as best I can describe it when you have load on the truck. LT tires wont do that at all or nearly as much. To give you an idea, my F150 had a recommended PSI of 36PSI, my Ram 2500 its like 70PSI.
BOTH options however will change your ride a little empty, just warning. The RAS didn't change it that much but it was a hair stiffer in the back end, but again, cornered better. Ford puts P rated tires on there to make the ride better, I am convinced.
Nothing has been as drastic however as going from a 1/2 ton to a 3/4 ton, the 1/2 ton rode so much better empty, there are days on rough roads as my daily driver I miss my F150.
2016 Jayflight 29BHDS
2015 Ram 2500 Laramie Crew Cab - 6.4 Hemi
2013 Ford F150 Supercrew EcoBoost, MaxTow (Loved and Sold)
Equal-i-zer Weight distribution system