Wolves may be strong and fast for Tyraxor, but to get improved wolves, you also need to improve the goblins...
Actually, a strong dog stack is a thing in The Succession Wars. That's why people start with Tyraxor with three wolf stacks, which can be upgraded to level 111 without upgrading the goblins.
And in Horn of the Abyss, people usually pick either Crag, or Gormak, and some take Dess.
(P.S. I don't know how to play Fortress and I don't like them anyway.)