when i see number of badges for different missions, one point come in my mind that there should be a badge for participants which automatically should be added when participants enter in 12 month leader board of any forum (marketing, sales, service etc..).
Because leader boards will be changing with time to time in future but the earned badges always be there to remember him/her and others that he/she was one of top (active) contributor may be some time back .
This came in my mind and just shared with you experts , just a suggestion
I see that you posted an idea around this in Idea Place:
That's the best way to make such mission suggestions, so you're on the right track.
Now let's see how many votes the idea receives.