Well we've run monthly challenges in the past that were "create map symbols for a specific theme". While it was a while ago, November 2007 was create a set of Old West symbols which was the inspiration for my Superstition Valley map entry. Another concern, though, and I don't know how true it is now, or will be in the future, but we've had monthly challenges with only a handful of participants - if you have too many different challenges at the same time, it could affect who and how many are going to participate. Back when we ran the Old West Symbols challenge, there was no such thing as the light challenge - we only had a single monthly challenge back then, and when I participated in that one, I was the only entry for the first 2 weeks. I even begged someone else to enter, so I didn't have to go it alone. RobA finally participated, so there were just 2 entries for that challenge - and my first challenge win.

I'd hate to see the same circumstances occur, if we have too many challenges going on. Something to consider anyway.