What if 343 Industries had a contest to find games for double exp weekend. Where what would happen is you would send in you best custom game and a summary for a idea for a playlist. Then it would be reviewed by the 343 Industries team, and if it is really good they may have you test it with them.
Then if they like your games and ideas they will see if there is any other game types that could go with the playlist also. THis would really help 343 industries and the Halo community to become closer than before.