Yep, all the below ... and also ...
*UNCOOL ALERT*
If you find uncool music taste abhorrent, you may wish to scroll down.
My favourite pianist is ... Elton John! Great rhythm, great touch, great style.
Ok, it's safe to look now.
Also Steve Winwood was great with Spencer Davis Group, Traffic and with Stomu Yamashta.
I'm told that Art Tatum is the greatest jazz pianist player of all time but I know nothing about him. In jazz I love Dave Brubeck, Nina Simone, Cecil Taylor, Chick Corea (on electric piano), George Duke, Herbie Hancock on synths and, especially, Joe Zawinul.
In prog there are some great synth players - Eddie Jobson with Uncle Frank and UK, Stomu Yamashta, Eno, Richard Wright. Mirette Garaudy produced beautiful synth sounds with Steve Hillage. Can't forget Rick Wakeman. Keith Emerson is brilliant but can be grating.
Michael Cotton from The Tubes is an undiscovered treasure IMO. Thijs van Leer from Focus is brilliant at everything.
For organ, obviously Ray from the doors, also Greg Rollie from Santana, Dave Greenfield from The Stranglers,