Recruited Sigvald in my Archaon campaign and noticed that he doesn't have the Chaos Vanguard trait which buffs the marauder units, instead he has Fanatical Cultists to buff the cult unit line. I don't know if it's intentional or not, but it seems thematically that Siggie would have a buff for the marauder line and Archaon could get the option to buff cultists. Just my .02, love the mod so far, all the new unit models look great.