Ukraine had stable relations with Russia until they decided they wanted to align with the west and adopt democracy when there was a color revolution in 2014. If they had remained a vassal state of Russia, their relationship would still be stable.

Similarly, the situation in Kazakhstan is stable because they are a vassal state of Russia. Watch what happened when there was the beginning of a color revolution there earlier this year: Russian quickly sent troops to assist the Kazakh government in violently putting it down. If a successful color revolution was to happen in Kazakhstan (unlikely), Russia would be playing the same military games with them that they are now doing with Ukraine.