First off I have a 30ft travel trailer weighing in at 6400lbs loaded for camping. Right now I have a 2011 f150 fx4 ecoboost 5.5 ft bed with max tow. Im thinking about a new truck but not sure what to ...
I would not change your 2011 F-150 for a 2014 F-150 unless there is something wrong with it or you want different equipment/trim. There are no significant changes except fuel tank size for 4WD. Save pennies for a 2015+ or enjoy the lower cost of ownership for the next 5 years.
Your 9k non-towing miles are no significant enough IMHO to warrant a half ton compromise in stability over a 3/4+ ton. So if you want an HD, get one.