APS has no direct relationship to ELO. The APS can go up because, as you said, a lot of weak bots were added. For ELO not the pure result counts, but the result relative to the 'expected' result. If f.e. the expected result is 95-5, and the true result is too, ELO would not change, while APS will go up. For me, an ELO of 2000 for cf.proto.Shiva 2.2 would be acceptable, as it hoovered there in 2006-2008 (source: The 2000 Club). That means that -280 would be even a better pick in my opinion. Ofcourse that would not be ideal for every bot, but I think that setting the border for The 2000 Club as it used to be (long time ago) is a good compromise.