Legit puzzles as a regular part of gameplay. It's one thing to go on missions and have to take objective A and recover that important doo-hickey or thing-a-ma-bob, but in a dynamic universe, that can get old really fast (think Spartan Ops). To keep things interesting it would be refreshing if players are challenged to figure out some of the mysteries of the Destiny's Universe. I mean if puzzles aren't your thing, it doesn't have to be incorporated into everything. You can always wait till people figure stuff out. I just feel Bungie's always done a great job with their ARG's to build hype for their games. I would like to see them start integrating this into gameplay and make it dynamic, so that new ones are continually being added.