True about the AW needing to be a new chapter, so would settle for a dog-generating building, then as you say pompeywolf everyone could benefit once their training grounds were researched
Btw i use quite a lot of banshees as well as dogs from the training ground. They are so effective when the enemies are mostly heavy melee units.
I like the Elvarian Guards as heavy melee units in preference to the orcs, but maybe I have not found the ideal enemy for the heavy melee orcs!