My only complaint is that the verb 'to endorse' might be a little bit too strong. A button that says 'appropriate' might be better, because it's more clear then

My only complaint is that the verb 'to endorse' might be a little bit too strong. A button that says 'appropriate' might be better, because it's more clear then what exactly the intended criteria for an endorsement are and the user does not need to identify with clicking the button as much.