My initial point was a speculation (somewhat facetious, but not completely) that perhaps certain ballet-goers –– whether Russian-speaking or not –– are drawn to names that sound distinctly Russian. Kochetkova and Vishneva fall into that category; Part does not (and in fact is not a traditionally Russian name, I believe –– I forget her father's background). Even today, among certain ballet-goers, there is a certain veneration given to Russian dancers, especially female. My saying "if she'd been an -ova" was meant to refer to that. I did not mean to leave out -evas or any other Russian-sounding variants. It was a point about perceptions, not spellings.
I recall reading elsewhere on Ballet Alert that the end of Vishneva's name was properly pronounced -nyova (approximately –– not trying to be phonetically exact here!), but perhaps that was incorrect.