Lou Reed was a broody addict who just so happened to write poetry good enough to catch the attention of the New York art elite world. More specifically, he got in touch with Andy Warhol. They talked, planned, and put together some songs and released an album. Everybody wanted to be Lou Reed, his quiet demeanor and commanding presence on stage struck fear and love into the hearts of his fans. If he didn't die at such a young age, the Velvet Underground would likely still be popular today.
Marvin Gaye
Marvin brought more to the music world than just a different take on Motown. He brought love, soul, pain, and complexity to an otherwise stagnated genre.
When Marvin Gaye first started releasing music, he was the drummer of a band called the Miracles. After several years of being the back of the house for others, he decided to step to the front of the band and sing. His voice was unique, raspy, powerful, and driving. Marvin had the soul to make unforgettable music, and the stage presence to let everyone in the room know that he knew exactly what he was doing at all times. Additionally, his music had more sex appeal than literally anything else ever made, and he might still hold that title.
Brian Wilson
There are a lot of perfectioniosts on this list, but Brian Wilson might be one of the most emotionally complex. He poured his blood, sweat, and tears into every song he made, literally.