If I were in charge of a new series, the Prime Directive is one of the first things I would chuck out the window and start from scratch on. It would be very simple.
Essentially "No star ship commander shall involve themselves, or any member of their crew, or any starfleet personnel, in the political or cultural machinations of a pre-warp society." IE: Yes, you can save them from extinction, just go unseen. Don't influence the culture and politics.
As far as I understand the PD in TOS, that's basically how it was supposed to be anyway.