You want me to pick one.....
I starting thinking about this and then started thinking what is a rock ballad, to me it is a slow song with a bit of emotion, generally some sort of love song.
A few of my favs have already got a mention so I was trying to think of some others, for me, for personal reasons I can't go past the Hunters Throw Your Arms Around Me, there are heaps of versions (and covers Neil Finn did a beauty) but here is Mark Seymour.
Then again if you are talking ballads how can you go past Paul Kelly
always loved the Baby Animals as well, Suzi was my childhood neighbour,