Cool idea! 100% agree animation wise, it's weird to pummel a plank in place with your bare hands.
As for a tool, I would love to have it add more immersion (kinda like campfire+wood) but adding an extra step in repair could potentially affect drastically the flow of combat, but I guess it's nothing players couldn't get used to, like breakable parts and fire. (I'd expect some solo players to predict the death of soloing as with every changes).
As a weapon I really don't know, why have a sword if you could have 2 guns and a (potentially weaker) melee weapon as well?