one last BUMP and I'm off to harvesting the images from last month. Still waiting for comments on improving the selection process.
I think the top 5 vote getters is fine. The "people" have spoken by placing their votes in the competition. The contests run for 3 days so if an image is on a Sunday, then folks have plenty of time to go back and vote.
I think it's clear that the favorite images of the folks on the site are the ones that get the most votes. I've seen entries from a Sunday do as well or better (votewise) as any other day of the week.
So, I say leave it as-is. If you have a favorite that's not in the top 5 vote getters, then create yourself 5 aliases and start voting more for your favorites...