If you could bring back one great artist that has

Baka,

I hear you.

In answering the OPs question, I would not want to bring someone back into the same painful situation that resulted in their demise originally, that's all.

I chose Lennon because he appeared to have conquered many of his demons prior around the time of this death and his artistic output appeared on the rise again as a result.

Not interested in hearing artists wallow in pain indefinitely though I certainly can empathize with their situations. I need to see more evolution from an artist over their lifetime than that in order for them to hold my interest over the long term. But that's just me.

Also, Johnny Cash is another who fought many demons that helped make him a more interesting artist, but his legacy was much greater than being just another tortured artist.

@mapman. I'd like to believe if Cobain had still been around his music would have evolved. I can't necessarily say the same about Janis but I just loved her voice. Speaking of the 27 Club members, I wonder how Morrison would have progressed? Did The Rolling Stones of the same era ever really grow up? lol

Saw Janis a few times, very hit and miss. When she was on she was memorable and dazzling when she wasn't it wasn't worth the time.
Would like to bring Mozart into this. Another artist who was beginning to break into new venues or avenue of creation. What and how it might have turned out is as we all know to well is left unknown

Although not a performing artist, though he did play piano. Is Billy Strayhorn, who composed many of the hits for Duke Ellington. He died all to early at age 51 in 1967. We can only surmise the body of work that was yet to come. But nonetheless what he left behind is timeless.

Ian Curtis, Joy Division. i think we only saw the tip of the iceberg regarding Mr Curtis.