There was a study by Jane's about 20 years ago which said that Russia will eventually attempt to recreate its empire by absorbing the former Soviet republics one by one, but it would not touch the Baltic states until last. By that time the West would be powerless to stop them and will not risk nuclear escalation which the Russians would threaten in an instant.
The only wild card would be the Chinese. There is a huge region that both the Russians and Chinese claim, the Maritime Region which is the are surrounding Vladivostok. If Russia had nothing else to do and the West wasn't a threat, their next objective would be to take the Chinese areas back by force.
I dunno. Russia is going to have to start going after former SSRs that are now NATO members, and one of the little baltics might be a good first test case to see exactly how NATO is going to react.
The point about China is interesting. If the US & EU can muster up the will to put a serious hurtin' on Putin via real economic measures, that might weaken & distract Russia to the point where the Chinese decide that there are ethnic Chinese in Russian territory who now need "protecting." At that juncture, China could probably get away with it, too. Putin has made a very, very big bet on the weakness of the US and EU political will.