Remember just before the murder he said he had proof that Russia was sending troops to Ukraine. That is how you get shot in Russia. You tell the truth.
No, I don't remember. He made relatively little noise while alive, having discredited himself by plundering Russia during the 90s. Please give reference. My impression of him is that he was not stupid. If he indeed had some damning evidence, he would have ensured himself by standard practice that in case he dies, everything becomes publicised.
Oh, and there is nothing suspicious about that Ukrainian girl, who comes the day before the murder, lures him onto a deserted bridge, and then doesn't see anyone shooting Nemcov, and remains alive herself, when in such cases those who are close by are killed as well as per the practice from the 90s. Nothing to think here, move along...
Apropos 90s:
http://stanislavs.org/for-russia-90s-were-worse-than-wwii/