Well if you feel you have enough time with all the other stuff going on, I don't see a problem in you organising the threads.
We could keep the section moderated so that we can make sure only you are creating new threads in there. It might be an idea to let people with different games to you set new challenges every now and then because not everyone has the same games
Apart from that, I think regular challenges every week, fortnight or month would go down very well!
I'll pass this thread onto the elders and see what we can get done.