Central Asia, no (although China is actively making inroads there).
But there's still Armenia, Azerbaijan, and Georgia to consider. These aren't Slavic, but they are of interest to both NATO and Russia. Well, Armenia is pretty firmly aligned with Russia for historical reasons and some semblance of security against Azerbaijan and Turkey. But the other two are already Western-oriented, and Georgia has applied for NATO membership in the past.
As far as Slavic affinity, it's a bit more complicated. For example, Bulgarians are Slavic, and Eastern Orthodox even, but being on the wrong side of WW1 and then WW2 vis a vis Russia/USSR overrides that. OTOH with Ukrainians, many Russians outright deny that they even are a separate nation or ethnicity, and claim that it's just a sub-branch of Russians who speak a dialect of Russian. From that perspective, occupying Ukraine is described as "re-unifying" Russia.
But there's still Armenia, Azerbaijan, and Georgia to consider. These aren't Slavic, but they are of interest to both NATO and Russia. Well, Armenia is pretty firmly aligned with Russia for historical reasons and some semblance of security against Azerbaijan and Turkey. But the other two are already Western-oriented, and Georgia has applied for NATO membership in the past.
As far as Slavic affinity, it's a bit more complicated. For example, Bulgarians are Slavic, and Eastern Orthodox even, but being on the wrong side of WW1 and then WW2 vis a vis Russia/USSR overrides that. OTOH with Ukrainians, many Russians outright deny that they even are a separate nation or ethnicity, and claim that it's just a sub-branch of Russians who speak a dialect of Russian. From that perspective, occupying Ukraine is described as "re-unifying" Russia.
(Source: am Russian)