Which eco-boost? The 3.5 will have plenty of pulling power and the turbo will handle altitude much better than a naturally aspirated V8. It won't give you the engine braking of a diesel but that's probably overkill.
Assuming 12% tongue weight (1188lb), you better be a 98lb weakling or you are over weight before putting anything in the truck. 1300lb payload is way low for pulling that big of a trailer.
Also, the 3.53 rear end is not a towing rear end. The transmission can compensate to a degree but not really the best option.
You are looking at at least a 3/4ton but if you are going to buy a bigger truck, seriously think about jumping to a 1ton SRW. Hardly any difference in cost and you get a bit more payload.
If you want to put the ATV's in the truck bed, you have to run the same calculations but in addition to the tongue weight, you have to include the weight of the ATV's (and other cargo) in the truck bed.