Was clicking around on the main census page when I got another idea, though I'm afraid this one will be hard to implement.
What if you could focus the census information on a specific (user submitted) level range?
Say two fields where a visitor could enter "50" and "60" to get the census for the level range from 50 to 60.
Would be interesting to see how the classes (and races) attractiveness develops across the levels and/or if some classes are only favorites at the lower end of the level range which has now ~80% of the entries.
Anyway, love this site =)