the author of this thread doesn't know anything about ex-USSR countries. Ofc, Latvia is not CIS, same as Ukraine. But it's CIS in our minds, like Belgium+France. Yekindar speaks russian as a russian citizen, so he should be on that list
I would say about 30-40%. In my area about 20%. Those who lived in USSR knows russian (obviously) so mostly older people, my generation doesn't know the language that well, or at all unless they live in russian speaking family.
Hobbit, Ax1Le, Electronic and mir for CIS.
YEKINDAR plays in a CIS team despite not being CIS himself, so he is up there also. Obviously s1mple being one of the absolute best is up there also but he's mostly an AWP-player so I guess he is exempt from listing those strictly to rifle-roles.
EDIT: Typographical error.
Hmmm, Electronic seems to have been through a slump. Although he's recovering, I would not call him best. That leaves ax1le and Mir as contenders. Both are awesome, but I think Ax1le is more promising for the future. So, that's my answer.