I would like to see how many people have completed every achievement, average gamerscore, etc.
Also, I think it would be really cool to have a medal for having every achievement 
That would be a cool feature. See how many people have earned all the Halo achievements. I really wish they would include Halo 2 Vista achievements.
That’d be a great feature
A pretty nice idea
I would definitely support that because I’m a achievement hunter 
It would be awesome to have a global halo achievement leaderboards.