The language is a very big problem, at least in the company I worked with for over 1,5 years, and it is not so long ago. About the pilots there are of course many who speak good enough english, but there are quite some pilots who did not speak well enough english. Just last week I flew with a russian carrier (a/c was an Airbus) and none of the cabin crew spoke good english.
But for the technical staff, the mechanics working on the aircraft, here the language situation is really bad, in the company I worked for maybe 10-15% of the mechanics speak english well enough to understand the manuals.
I don't want to say that everything in the russian aviation is bad (I only worked with one airline), but what I saw there was so bad that I would never fly with this company again.