Hmm, I think your idea makes sense. Reward out-of-the-ordinary content more heavily. You could put a filter of some sort on it until an account has enough history to make a valid calculation.

Another potential workaround would be to intermittently bid-bot your post to get some posts way above average.

So the idea is to reward the discoverers of content.

I think another important factor will be the vote weight. If you are just spreading 1% votes everywhere, then you don't believe in any one piece of content very strongly and just trying to game the system. But if you spend 100% votes, then this piece of content is in your top-10 for the day.

I'm sure there are more factors to consider.