When I implemented ranks on Classic, it was a ****ty system (at least based on some code I probably wrote forwarded to me upon request). It was also used for PKs, but I haven't re-analyzed the PK bit as much.

The number of spar points relied solely on the rank of the player you defeated and declined logarithmically. It makes sense until you consider that certain cliques spend a lot of time sparring and could run away with the most spar points.

I still like the concept of logarithmic point assignments, but think that the gains should be based more on difference in rank between two players rather than solely the rank of the opponent. That way there's diminishing returns for the top ranks and the maintenance of greater returns for lower ranks defeating top ranks. Then again, I'm pretty sure my ranks were a competitive failure, and before I had the code forwarded to me, I thought that this was how I implemented it.

Have to ask, how's it implemented these days?