Two other things on unsubscribing. One as an spam detector I use a different variation on email address for every site I ever sign up to, so "reply to unsubscribe" sucks (I note that you said a link, which I like).

I have been stupid enough to push a unsubscribe link by mistake. I prefer that it automatically unsubscribes me rather than having to push a button to confirm, but it is not a bad thing to also have a Whoops I made a mistake button.