Crossbows are fairly powerful as they are in game. How much have you toyed around with them and the variations? I say they’re powerful for the following reasons.
The bow is fantastic and can stand well on it’s own early game, especially when you can get a brother up to 70 ranged skill. It’s not all that fantastic when it comes to fighting armored units though. A double tap on an orc warrior or a hedge knight does laughable damage even with a warbow. Overwhelm might be useful in this case, but you wind up bringing a longbow unit capable of laying down rapid but ineffective fire when you could have brought a crossbow/backline specialist who can utilize armor penetration.
There are also two variations above the mid tier crossbow that are very strong. The heavy crossbow has increased armor penetration, and the crossbow that you can get from the goblin overseer (I forget the name) even adds knock-back to the already powerful equation. Late game I’ve had crossbow units that can out right kill a unit and heavily wound another through strong armor in one turn once berserk and fearsome have been unlocked. Berserk on its own can very strongly increase damage output even if you have to spend the next turn with a reload.
The +15% increase to hit chance and the armor pen capability is what makes crossbows powerful. With the crossbow mastery perk, the armor pen value even jumps up to monstrous levels for the previously mentioned high tier crossbows.
The longbow is fantastic for lightly armored units, but the crossbow is a must for heavily armored unit types. Either way, a heavily trained ranged unit is easily an mvp. I know there’s a bit of debate on the forum about specialized range. I like them. I’ve had engagements with 2 longbow specialists where “plethera of orc young” don’t even make it to the shield line. When an orc warrior is a part of the equation though, I’d much prefer a crossbow.