Well, just couple of thoughts

[Kriegstofu]

well nowadays we have the problem of more grinders than halberdiers so there has to be some usability fixes on that. as Halberdier has around the same armor as Crossbow heroes i assumed that it would fit best that role, Armor Wise its Archer/SKirm/Xbow/Inf. with halberdier lying between Skirm and Xbow armor Wise.
Also as there are Fewer Xbow Bots than other Type of Bots, the chance of Heavy Sallets to drop is fewer than for example Barbuttes (Nord Vet Pikeman) or Ornates on Einherjar Pike (thats hard and rag bots) whereas Xbow can only loot Helmets from Rag bots (Dvergar/SM?)

Or Maybe Zweihander/Legi?