He did for the piano what Chuck Berry did for guitar. He brought it into the Rock 'n' Roll family. Before Berry, guitar was a blues or country instrument. The early Rock pioneers sounded like bluegrass players. Les Paul was influential, but Berry turned the sound of Rock on it's head. And that's pretty much what Little Richard did for the piano. Fats Domino brought the piano to Rock, Little Richard made it badass.
He was the first Rock sex symbol. He was controversial because he was black, and when he played he played like his hands were on fire, and shouted and screamed like he was having an orgasm. Seriously. The man was a freak. I mean that in a great way. Imagine listening to Pat Boone with your folks, all safe and sound. The next song comes on, and it's a crazy man shouting "A wop bop a loo bop a lop bam boom". Forgot your faux shock artists of this generation. Forget Marilyn Manson, Eminem, Lady Gaga. The impact Little Richard had on culture and society was a million times more shocking than drunk, slutty Ke$ha could manufacture. His songs were full of gibberish (like the above mentioned famous cry to introduce Tutti Frutti) at the time that gibberish was seen as carefully disguised sexual dirtiness and innuendo. People would have been freaking out. Little Richard was going to corrupt all the white kids. He didn't of course. But if it wasn't for him there would have been no Public Enemy, no OutKast, no Hip Hop.