ATC. The founder and owner is an engineer and jazz pianist. Realistic piano was a major goal of their speakers. Up until the time ATC got going, the Quad EL 57 was the most realistic sounding speaker for everything but it lacked bass, dynamic range and high enough SPL output.
ATC 150ASL should be on your audition list or just buy them unheard and you are done. Diana Krall uses ATC. You don’t need a power amp as they are active. There is a mint pair for sale currently in UK for just under 10,000 GBP. There is no doubt that these will do piano realistically (and everything else).