I think it's because we were watching the story from Jack's point of view. The people in the church were the most important to Jack in the story. Miles, Daniel, Charlotte, Danielle, and Alex were ancillary characters in Jack's story, whereas everybody in the church was with Jack through the most important part of his life, up to and including his death. I think it would have been fantastic to see Vincent there in the church, since he was there at the beginning when Jack opened his eye after the crash, then there with him when he died.
As for why Daniel didn't flash on Charlotte...no idea, I was wondering the same thing. I really wanted to see the two of them together, I always felt their relationship ended poorly.