My view, if any... kinda contrasts with the persone you see Link to have, but that's a very good answer aye.
To me he's more like, like you say a withdrawn individual... But not timid. If someone calls him a name he'll say nothing and brush it off his shoulder for not caring, but wouldn't bite back.
When it comes to crunch he's serious, not one to crack a joke, but not one to punch someone unless they were attacking him first.
I wouldn't say he's timid though. Lol.