I am 61, and have been listening to "rock" or "pop" or "alternative" for 50 years.  I still buy music, and have seen the Cure, Arcade Fire and Radiohead live over the past few years.  Needless to say, I have given this a lot of thought.  My answer follows.

 In a class by themselves, and roughly equal in my opinion, are the three already named.  Each of them, in their turn, brought into existence a whole new sub-genre of our music.  (It is a measure of AF's greatness, in my opinion, that I can include them after two albums.)

 Following the "big three", in rough chronological order, are:  a) the Doors; b) Pink Floyd; c) Roxy Music; d) the Clash; e) Joy Division; f) Ride; g) Placebo; and h) Interpol.

And yes, I know there are 11 named.