At this stage of the game the only threat are those heavy armored orcs. Ranged brothers are bad against those so I would say archers are useless. But dont get blinded by those orcs, I think devs have something nasty comming to us in future. So you will need those archers to win those battles.
But yea at current stage I dont put points in ranged attack. Tbh I havent had chance to try out javelins. And if AI gets better scripts and understands it has advantage at ranged combat they could just take good defensive positions and force you to attack. I would like to see some skirmish combat front of the lines to really make other party to be forced to attack or retreat. Mb increase the range of bows.
