Unbelievable. Staggering actually. You are taking solace in the fact religion has killed only 30M. I assume you're including the recent deaths of millions from Aids in Africa in those numbers due the catholic church's refusal to allow condoms?
The Atheists you mention didn't kill in the name of Atheism.
As for the black death...I'd never before considered assessing the merits of religion by comparing to a bacteria. You might be on to something though.
The Russian Orthodox Church and Tsarism isn't Atheism either.