I built a script to move the data out of global variables. This was required to make co-op (and other) categories possible.
I followed the D2R category structure. Probably good to have similar category setup for the two games anyway.
With current setup any kind of change is fairly easy and definitely possible. Adding new categories is also not an issue, because there are no global variables that get in the way.
I also already built the co-op leaderboard and would also like to add the Twink category.