Looking back at my sales data, in 2016, AT-AT was definitely the star of that group for me with a gross profit margin of 220%. ISD and Ghost were both in the 110% range, but I sold the Ghosts early.
Since that round of retirements, in 2017, my highest margin SW sets were Imperial Troop Transport (121%), Hailfire Droid (102%), and Jango Fett buildable (126%).
However, in the year before I sold that round of retirements (2015), my highest margin SW sets were AT-RT (147%), AT-TE (110%), and Mandalorian Speeder (100%).
Over each of those years, the remainder of my SW sets had margins in the 75%-99% range.
From my perspective, AT-AT was an outlier in terms of performance, which is understandable given its iconic status. Also, I can see TFA have any noticeable impact on the SW market, at least through FBA. Obviously, a lot of that has to do with the sets that I stocked so it may have looked different if you were loading up on completely different sets.