This is not meant to praise Soviets in any shape or form. People keep comparing Putin to the USSR and I think he's more aiming for tsarist Russia. Which was generally even more draconian and repressive than the Soviets
Maybe. Tsarist Russia was earlier than the USSR, and so the Communists were perhaps in ways more enlightened simply by being more modern. However, in terms of repression, I don't think they changed very much and it seems to me the USSR pretty much just continued all the same habits of the Russian Empire: strict political and ideological regulations, pervasive and heavy secret police, Siberian exile, etc.
That said, I think you are right in a sense. Russia surely would not hope to expand beyond Soviet borders, but in order to drum the Baltic States and Ukraine into line, it would have to carry out staggering repression - effectively, to aggressively wipe out their national character and Russify them. At worst, of course, they could just be deported and scattered to distant parts of Russia, then repopulated by loyal Russians.
In terms of the latter, there have been reports of Ukrainians forcibly removed from the Donbas by Russia, potentially in the hundreds of thousands. This could easily be de facto ethnic cleansing. If we imagine that at some point Russia does manage to get a referendum in the Donbas states, if it has removed a huge chunk of the Ukrainian (loyalist) population to refugee camps or resettlement elsewhere, it is vastly more likely pro-Russian separatists will win any subsequent votes without needing to rig the vote at the ballot box, and effectively take those areas over. Which I'm sure Seanchaidh would praise as a great victory for democracy and fairness.