"Landover Baptist's Christian mole in Hollywood says that most of the early story lines are going to revolve around Scott's faith in Jesus Christ. "He has a powerful hunger to share his superiority with other species," the mole reported... Insiders say that churchgoers should expect the new series (at least the first two seasons) to be much like an intensive one-year Sunday school lesson."
I suppose a "one-year Sunday school lesson" might explain why Enterprise only has 4 episodes left. However I think it might have more to do with poor stories and uninteresting situations.