10 speed F150 axle ratios

I'm considering a 10 speed F150. My '13 3.5 Ecoboost 3.55 axle 2WD Supercrew short bed is darn near perfect for my one and only cage transportation and tow vehicle. It performs very well. I have weighed it twice while towing. Once the toy hauler was 6700 lbs. with 780 tongue weight with GCW of 12,920 and once it was 7100 lbs. with 800 tongue weight and GCW of 13,260. On the first one the rear truck axle was 50 lbs. under the GAWR and on the second time it was 70 lbs. over the GAWR. In both cases there was some cargo in the truck that could have gone in the camper. My only reason for trading would be to get a little more payload. The '13 has 1607 lbs. payload and is rated for 15,300 GCWR.

For the configuration I want, the only two axles available for the '17 are 3.15 and 3.55. It looks like with the 10 speed transmission, the 3.15 axle 1st gear is about the same as the 3.55 axle ratio with the 6 speed (equivalent to a 3.54 actually). With the 10 speed, the 3.55 1st gear is the same as the 6 speed would be with a 3.99 axle ratio. The 3.15 has a GCWR of 15,800 and the 3.55 has a GCWR of 17,000 (max tow). It looks like I would get about the same towing capability with a 3.15 in the 10 speed as I have now with a 3.55 in the 6 speed. Actually the 3.15 ten speed is rated for 500 lbs. more GCVW. What I have now is fine with my rig weight at about 87% of GCWR. I'm thinking maybe I could go with the 3.15. What do you think?