Here is my RYM "Wishlist", which has every album I want to listen to at some point. There's near enough 500 on there. I will say over half of those will turn out to be bands/artists who fall under that category.
The most recent artists/bands I have actually listened to that I wish I had heard earlier are
Catherine Wheel,
The Church,
Peter Brötzmann, and
Ultra Vivid Scene.