Whenever, as a filmmaker, you try to intentionally pigeonhole yourself into telling a story a particular way and you don't allow the natural course of change that typically comes in filmmaking, the less impactful your movie will be. Movies rely on emotion, and the thing that faith-based films have yet to do is to expand beyond the church going crowd because non-church goers are turned off immediately when they see the trailer. Now, I'm not saying stop making the Kirk Cameron movies, cause there is a crowd that enjoys them, but if you're wanting to impact non-Christians with your movies, then you have to think outside the box and not beat them over the head with a sermon.
How you're going to impact non-believers, is through simply telling a good story, and not necessarily setting out to try and accentuate a spiritual theme. If, as you are making the film, a spiritual theme surfaces in your story, then that is real dandy. The thing is, as a filmmaker, you bring your own baggage to the filmmaking process, and your own beliefs and values will impact your work. If you are a Christian, and you have a certain set of ethical values, then you're most likely going to apply those values to your work.
We live in an age where the media has such a profound impact on the normal man, woman, or child, and to be honest, most of it is ethically negative with tons of innuendo, cussing, and violence. If you have a certain set of values and just simply apply them to your story, you'll be surprised to find that your story will be an ethically positive story, and that is how faith-based films I think can take a step forward from the church crowd to non-Christians. A good movie, an impactful movie, is not a movie that beats one over the head, but is a movie that relies on subtlety. Faith-based films don't have to be an extension of the Sunday morning service, as I said, there will always be a need for such movies, but there also needs to be movies that just show a positive lifestyle. There will be problems in any life, it wont always be sugarcoated, but if a Christian makes a movie, and applies their values to the story, then the audience will see how they view the world and how they live, and that is the future of Faith-based films.