Our last trailer had a fairly heavy tongue weight (1100lbs, 6300UVW, 8200GVW). It was one of the double over double rear bunk plans which meant that we had a huge storage compartment in the back under rear double bunks, so I wasn't initially concerned too much. Nothing I did (e.g., tools and cast iron in the far back of the storage bin), seemed to lighten the tongue appreciably and definitely never got it even below 1050lbs. My 2008 Tundra Double Cab 5.7L (1436lbs payload) could physically tow it and did a fair job of it, but according to every number and weighing that I did, we were over on payload by about 400lbs once the family (wife, two and two dogs) was loaded in.
My fix was to upgrade to an F-250 diesel about a year later. Towing experience was about the same, except that the F-250 doesn't even break a sweat going up steep hills. The mileage was considerably better too, going from 8-10mpg to 12-14mpg.
I was more careful when we decided to get our Octane. We're near the line, but definitely on the right side of it this time around.
2015 Octane T32C
2012 Ford F-250 Lariat/FX4/Diesel