What Kurts death did was make them even more explotable so yes i have to say they went from famous to legendary after that and the myth that kurt was murdered only adds to that. Like jim morrison or Sid and Nancy its all part of Rock 'n' Roll. I think if Kurt was still alive he wouldnt be performing anymore maybe a producer or a song writer. He did once say thats what he would like to do.

People always seem to interperate the whole setting surrounding the MTV unplugged performance as "like a funeral" and "kurt was almost singing at his own funeral."
I disagree with that strongly, I think that Cobain had envision a funeral, but not for himself. A funeral for Nirvana. He wanted out of the band there was no denying that. I couldnt see how he would kill himself. Dave Grohl stated that Kurts outlook on life changed after his daughter Francis Bean was born. I guess we'll never know that though.

Personally though, those last lines on the suicide note always bothered me...