Is It
Massive Attack:
nontraditional musicians as soundscapists using reggae/hip hop/avant garde production techniques
But then Throbbing Gristle, Caberet Voltaire, Suicide
My Bloody Valentine
Sonic saturation built upon Sonic Youth/Branca
Sonic Youth
Sonic satuartion built upon Glenn Branca
Slint
1st post rockers
Pixies
continue the punk mantle
Nirvana
continue punk mantle with noise/metal or is Mudhoney, Green River, etc
Joy Division
huge influence now and on grunge bands
How about Siouxsie and Banshees plowed similar ground as JDivision?
Julian Cope
More influential now as writer and Urmetalist, then as a traditional melodicist
Actually there are a lot, I don't know if there ever is any ONE most influential at any given time.