[Wrana]

For thug commanders I will also vote for Wraith Lord. Though I also like Air Queens. Spectral Mage is excellent to provide access to any paths. Faerie Queen is invaluable as it provides healing.
As for troops I liked Pale Riders until they were moved to higher research level. Another good troop are Claymen I think. Iron Dragon at higher levels.
And - currently - Buried in the Ice!! Even troopers are almost thugs, while shamans have good path access & may be turned into very good thugs indeed. Not ethereal, though.. But this mass of good troops is worthy just the same..