Suggestions for a TT for a 2015 Expedtion EL with ecoboost

I just purchased the same vehicle as you, because my suburban was not towing my jayco 26bh very well. The suburban had the 3.08 rear axle and was a pig on hills. So far the Expy is night and day difference then the burb. The jayco 26bh dry is about 4800 and max 7000 when fully loaded. the dry tongue weight is under 500lbs. I wouldn't want to go any heavier then this. We have four children, the bunks in the 26bh are huge, each one can sleep two kids easy(as long as the get along well).