In the past few years, I think small sets have really been my favorites. FRF was my favorite in the Khans block. OGW beats BFZ, EMN beats SOI, and honestly so far I prefer HOU to AKH. Kaladesh is the only exception, since I found AER forgettable.
In general I hope the switch lets them draw on the some of the strengths of small sets - the more "out there" mechanics, a less "introductory" feel to the creative, the iterative design. Like, instead of teasing out a mechanic through two/three sets, getting more creative with each step, just put the pedal to the metal from the beginning.