While the idea is fun, I don't play archer and this kind of thing would hinder knights/builders/movable weapons quite a bit. I don't think they should be able to latch on to siege weapons, but I am fine with builders and knights so long as they have more force than an archer. Example, some skinny little archer latches onto this muscular knight in heavy armor, that archer is not going anywhere. The skinny archer gets some buddies, who latch on to this poor knight and hang him from the rafters after turning him into a bloody pincushion. This kind of thing is fine, but not one archer negating all the force a knight puts into running away. Hell, here is a perfect use for rope actually, allowing archers to attach something to an object/block after grappling it. Of course, there would have to be some mechanic of the rope snapping when enough force is applied/it is hit enough, or else archers will just do a drive-by grapple and attach to stop a team of knights from getting anywhere.