You're right, I don't have much of an argument for relational databases here.

I am concerned about the complexity of this approach though and I don't think the concessions we're doing away with are that terrible. How meaningful is it to be rank 5623 vs. rank 5249, or even rank 2519? I don't think people can make much sense of ranks beyond 100, but maybe I'm wrong. I would rather break rankings into smaller groups. Which is more interesting, being ranked 23,528 worldwide, or being the town champion? I think the latter is much more meaningful to a person.