In the late 80's, there were plans for a Star Trek Academy film featuring John Cusack as Spock and Ethan Hawke as Kirk. The story behind its cancelation.
Cusack from Sixteen Candles and Hawke from White Fang with backdrop from Star Trek '09
Personal dream casting from that era: Ewan McGregor as Scotty, Emilio Estevez as Chekov, Tatyana Ali as Uhura, Brendan Fraser as Bones, Bob Saget as Sarek, Alicia Silverstone as Nurse Chapel, Ernie Reyes Jr. as Sulu, Jennifer Connelly as Una, and Jim Carrey as Pike (w/ Ace Ventura hair)
This episode reaches Ben Stiller levels of uncomfortable at times with regards to Spock being called out for his strict use of logic. And then there's the giant Neanderthal-like aliens.