But surely having Spock in it would be more of a stigma than not? Spock is associated by the general Star Trek hating public as a nerd icon. Somebody that nerds like. The type of people who make "hilarious" jokes about people living in their mother's basement (NEVER GETS OLD!) would be turned off by a movie with Kirk and Spock in a way they wouldn't have been with new characters and no Vulcans on the bridge.
It's fun to speculate.
Well that movie exists and those people were not turned off, no speculation is necessary.