From experience running forums elsewhere I can tell you that would be a bad idea. When you get too many sub-forums it starts to make the community look empty and less trafficked than it actually is. I don't know what the daily post count is here over all, but it's relatively low as forums go. The search function is there for a reason, and it works very well on this forum. This forum seems to have a good balance of new posts in each new category daily. Having a front page full of stale last posts dates would detract from activity elsewhere becasue this would look like a ghost town.