Too late.
With that many poison traps and crawler caltrops deployed, my grandma's cane would be able to kill those pipeworkers. I ain't sold on jack shit. Literally any other ranged weapon would also kill them, and probably faster.
I played a Crossbows build many years ago, before they were buffed, and my biggest issue (other than shit armor penetration) was their Godawful accuracy. They have less optimal than an AR and no dedicated scope slot, unlike a sniper rifle—so if you use a scope, you get one other enhancement.
A dedicated scope slot would, all by itself, bring Crossbows up to par. There is also no reason not to have one other than game balance; I've used crossbows in real life, and all of them that are worth a damn have a scope attachment rail/hardpoint, which doesn't require sacrificing other components. Crossbows in Underrail are not good enough to be denied a scope slot for the sake of game balance, so there's absolutely no good reason for them not to have one.
Pretty much the entire justification for their reduced range, lower optimal, and no scope slot is that they can kill silently at range, and yet you will still end up in pitched battles on the regular, because they can't powernuke an entire small roomful of dudes like a silenced SMG can.
End of rant.