Don't forget that Machaka has good access to fever fetishes (which go very well on disease-immune mound kings
).
And yeah, the Spider Knights are strong cavalry archers that can be produced at any fortress, unlike the Black Hunters.
If you care about other paths of magic, don't forget that death magic lets you access spectres (D1, ?1, ?1) and nature lets you get lamia queens (random sorcery picks).