More knights of the White Wolf.
To have a couple of units of 5 as flanking units.
My CoU army has:
22 White Wolf Knights
20 Teutogen Guard
40 Warriors of Ulric
20 archers / huntsmen
10 hunting hounds
Lots of priests, the WW GM, Ar-Ulric and Boris.
I used to have Knights Panther and Wolf kin. First I made wolfkin from converted 6th ed flagellants. Then I reclaimed them, and made them out of marauders, and then I reclaimed them too. They are a good idea, but I never really used them successfully in battle.
I believe the Middenland army can take cannon or mortars as Rare, but CoU doesn’t have them.
I also have 4 giant wolf riders - demi-griff rider conversions for 8th ed.