50% is a made up number. You got any proof that it isn't, apart from some book written by some guy? Nope
EU/US corruption can't be discussed along with Russian corruption? Why? Because it's more of a democratic type of corruption than the corruption in Russia? ))) If you think that they aren't interconnected in a globalised world, you're naive.
Nemtsov and Mishustin? Ok. So you really think that one man is capable of changing a political course of a country? ))