Hmm... Well, I'm very glad you came to us for help, you clearly need it. But don't worry, I'm here to make everything better!
1. Spreading the word and love of Jesus Christ is great and all, but unfortunately, there's not much money to be made in smuggling illegal literature. I'd suggest filling up the rest of the plane with drugs, guns and under-aged prostitutes. That'll help pay your way.
2. How about instead of planes, we use spaceships? And how about instead of Earth, they're all on Mars? Everything's better in space!
3. There aren't nearly enough hedgehogs in this game. Make the main character a hedgehog... Or better yet, a werehedgehog! (Specifically Shadow the Hedgehog.)
4. Finally and most importantly, this game needs far more rape, torture, murder and incest... Especially incest. (Ever since Game of Thrones came out, incest is all the rage. Your can't call yourself a writer until somebody's getting porked by their brother. Bonus points if they're twins. Twincest is wincest!) ^_^
So to sum up... Why are you asking people for suggestions when you obviously already know where you're going with this? You've already created a world and a plot and characters ready to make a game out of. Hell, you've already started to put the game together. If anybody did come up with any suggestions, they'd be useless to you because they'd all divert from the plot that you've already created. If you want help with something specific, ask for help with the specific thing you're having trouble with. Other than that, jut keep doing what you're doing.