And if we're going for say the top 20 "bloodiest" we should add (ant note their religions)...
Obviously you missed the point. The discussion was/is to do with religion being the cause/starting point of wars. So whether the leader was religious or not isnt relevant unless you can show that their religious beliefs are what drove them to war.
Leopold II for example was driven not by any religious beliefs but rather by greed, and the desire for power and recognition. He was the founder and sole owner of the Congo Free State which he exploited mercilessly. Note: it was Christian missionaries who first alerted the world to the atrocities being committed in the Congo, and it was the sustained pressure of missionaries, churches, The UK Government and most importantly of all the Belgium Catholic Party and the Belgian Labour Party that eventually forced Leopold II to hand over control of the Congo to the government.
I assume you included Kaiser Wilhelm II primarily as he was leader of Germany when the Great War broke out. By singling out the Kaiser and Czar Nicholas II you seem to imply that Germany and Russia were the ones who were responsible for the Great War. This is simply untrue. Yes both nations played their part but to varying degrees so too did Austria, Serbia, France and the UK. It is infact a matter of historical record that Kaiser Wilhelm II tried to avoid war. This is evidenced in his communications with Czar Nicholas II (who also wished to avoid war) and also in his instructions (after Serbia's reply to the Austrian ultimatum) telling Austria that there was no longer any justification for war and that they should cease further action against the Serbs. The reality is that the actions (and inaction) of both the Kaiser and the Czar were not influenced by, never mind driven by, any religious beliefs. Instead they were driven by secular issues.
Anyway, cant be bothered going through the rest you named.