The game team is shooting over data that is a table of rating -> rank that they use for rewards and for determining things that are outside of the top 1000 players (It's dynamic, updated at the same time the top 1000 ladders are). I'm going to make a new API endpoint for this data. I'll post here once it's live.
Using this and the pvp data in normal profiles you can rank players, but I did confirm that right now the game servers don't store more than the top 1000 in full ladder format.
I have pushed this thread over to the pvp designers and they do know how you feel. Right now they said to just expose everything we have so this table combined with the top 1000 ladders and profiles is it... we'll work on it more in the future.