Hrm! Some tips: From Archer what you want, mostly, are Hawk's Eye, Quelling Strike and Chameleon. Actually I am fairly sure they are the only even remotely useful ones as the WSes can't start combos at melee range.

From Lancer you might want Invigorate, Blood for Blood and you will definitely want the Cooldown Reduction one I forget the name. Once again, taking WSes from other classes is not that useful, I don't think.

So yes, you mostly want to pick up non-WS abilities that are usable by Disciples of War, give some though to them and see what appeals to you most