The day-to-day realities of ruling an empire as large and diverse as Russia probably requires the Russian state to come to some kind of accommodation with its Buddhist and Muslim minorities. I don't see much reason to go after Kazakhs and Tatars.
Most political energy would probably be directed toward persecuting Jews, reclaiming Russian lands in Kresy and the Caucasus, and stamping out the national consciousness of slavic minorities.
It makes sense for Russia to "unify" the orthodox slavs by treating Belarusian and Ukrainian of Russian and promote the view that they are parts of a larger Russian nation. Removing the Soviet's interwar policies that attempted to mollify national aspirations would drastically change the history of Ukrainian nationalism, Belarusian national consciousness, and Polish foreign policy. OTL, the '20s were something of a
golden decade for Ukrainian culture and national consciousness in the USSR.