We gave that some consideration, but the queries weren't all that interesting. The vast majority of those lists (something like 80%) consist of people with only one post. To illustrate this, here are the top tens for those queries:
Would be neat to be able to see the pps and ppc values for an individual... I don't make either of those lists, but I'd be interested what my averages are.
Interesting. Perhaps you could aggregate the numbers by time and compare the relative rates of change in karma and subissions for different time periods?