Very nice idea...

But I don't think that the competition should be changed after it already ends. The system you mention surely has its potential, but you have to take care of several things:

- I could convince some friends to make a crappy entry and give all their points to me
- The judgement of a competition has to be as neutral as possible. Your system is too easy to manipulate

Thats the first things I realize thinking over it.
In this competition, surely, I don't think it would be manipulated, because it's already over. But even if someone decides using it in the future, the above things still can occur.

Greetings,
Dirk