I know this isn't a popular idea but any thoughts on why privatizing them is a bad idea? It works in Japan. There are at least 10 train/subway companies in Tokyo alone. JR, Tokyu, Keikyu, Keio, Odakyu, Eidan, Seibu, Tobu, Toei, Keisei and they seem to be best in class by most measures.
No such culture exists in the US.