I think the pendulum has swung too far away from the voluntary voting system. I strongly recommend letting the user limit their voting to a random set within a specific genre or one or more user-defined genres.

I have no interest in nature photography and so if I encounter a photo of, say, horses frolicing, I'm inclined to vote highly negatively regardless of whatever photographic merit it may have, simply for being a waste of my time. Yes, from the aggregate of my votes and those like-minded you can infer we don't want to see photos of horses, but there are far less time-intensive ways to gather that.

In terms of functionality, if I have to see the full-sized image before I can give feedback then lop off the side navigation and just show me the full-sized images with the voting buttons on the bottom and top. Alternatively, consider showing somewhat larger thumbnails, and weighting these partial views differently. Radio buttons are also a bit of a nuisance.