Shatner isn't going to win new fans. I liked him don't get me wrong. He had a unique take to acting to put it lightly, however I don't think he's going to win any bonus points fot his movie. Most younger people I talk to cannot stand Shatner if not because of his whiny youtube videoes but for his ridiculous acting style. While this is not my own opinion of him, i can't help but think that he would have a slightly worse effect for the movie.
And seriously, he's not in it. RELAX go complain about the sets more.
"It's worked so far but we're not out yet."- Leonard "Bones" McCoy