Maybe more fans would have turned out for it, I'm 90% pointing the finger at the secrecy more than anything else to be fair
I think that probably broke down as: people who hated the first one weren't going to come to the second one and the people who liked the first one were going to show up and see what was next. Regardless of white Khan or the secrecy surrounding him. I saw Into Darkness three times in the theater.
It's possible I am completely wrong though.