Please provide data for your assertion that Russia prosecutes computer crime less than other countries. That is, we have no reason to believe that what you assert is, if fact, true.
As to extradition, Article 61 of the Russian constitution specifically forbids the extradition of Russian nationals. Further Article 62 states:
The extradition of persons persecuted for their political views or any actions (or inaction), which are not qualified as criminal by the law of the Russian Federation, to other states shall not be allowed in the Russian Federation. The extradition of persons charged with crimes and also the hand-over of convicts for serving time in other countries shall be effected on the basis of the federal law or international treaty of the Russian Federation.
So, even for foreign nationals, extradition must be on the basis of a law that a) makes the act a crime and b) allows extradition or is with a country with whom Russia has an extradition treaty.
I cannot find a list of countries with which Russia has such treaties but I know the USA isn't one. Given the any such extradition treaty would be effectively one way (i.e. from the foreign state to Russia but not the other way); there is little incentive for any state to sign one with Russia.