you are a gun nut living in texas when the chinese army invades in the year 2025. You organize a militia to stop them from advancing into texas. From there the gameplay is basically an open world game where you have to take side missions to secure gun shops, story missions of all sorts where you have to take down chinese encampments and defensive missions where you have to ward off the intruders. I think it would be an interesting experience and certainly would demonstrate the need to uphold the second amendment. 

Also I know how patapon should end (this is not a spoiler this is and idea). There should be a third game having the same formula as 1 and 2 with a different people to fight and the same sorts of bosses, but at the end you should find texts that say that all the other types of people you've been fighting were infact also descendents of the paptapon and you destroyed them, not realizing that earthend was not worth the destruction of other civilizations. This message of peace would resonate well.

K, feel free to comment and tell me how my ideas are so horrible and how you're all geniuses