To some extent I would say our goal with the game was to be less revolutionary this time around, since things were more solid in general. I feel like that's what happened with 3.0 that made it so successful -- it was by no means as revolutionary as 2.0, but it was by far preferred by folks because it refined so many things while also extending a lot of concepts that had already been toyed with some in the 2.0 era (leading to golems, more capturables, more AI dangerous structures, etc). For AS, I think the scope of the champions is hard to understate, though, in terms of how that can change the feel of the game. It's just that aside from those, most everything else is a refinement or extension of existing concepts.
I'd have to say that TZR was my favorite expansion for a long time, but now I think that AS has surpassed that, for the above reasons, personally.