Well...
OK, I guess I don't have a clearly defined reason for not liking AA. It's just little annoying details.
Basically... I don't like how AA made similar units for each advancement path. I prefer to not have underwater moho mexes, and I prefer the Krogoth to be "countered" by the more level 2 units that ARM has.
I want more differentiation between ARM and CORE, and more differentiation between the different tech paths. Maybe X unit they to CORE is completely different from X unit added to ARM, but at first glance they seem almost completely parallel.
And also, I'm better at XTA.
