My theory is that the Yugoslavs are the more archaic Slavic people. Despite what Albanian nationalists may tell you; there is more evidence, conclusive to me, at least; that Albanians are nothing more than a Black-Sea people. And there was no Slavic invasion in 6 AD. (It could be; that Slavs are Dacians or Thracians, or related. Which would explain why both tribes and languages went extinct around these centuries; while the Slavic people were first written about during 5th or 6th AD.)
It is for this thread about language (not for I2a).
Because some people thought Balkan hypothesis is plausible. According it Albanian language could emerge somewhere in the Balkans.
But new papers shown that it is not true. According Haak, Lazaridis, Patterson et al. Balkan hypothesis is not plausible.
Interesting discussion was several years ago, one Armenian member and I explained that direction of IE could go from Armenian plateau but some other members thought that direction IE was from Balkans to Armenia.
And Haak, Lazaridis, Patterson, et al. argue:
"The Armenian plateau hypothesis gains in plausibility by the fact that we have discovered evidence of admixture in the ancestry of Yamnaya steppe pastoralists, including gene flow from a population of Near Eastern ancestry for which Armenians today appear to be a reasonable surrogate (SI4, SI7, SI9). "
"Examining ancient DNA from the Caucasus and Near East may be able to provide further insight about the dynamics of the interaction between these regions and the steppe. Our results show that southern populations diluted the ancestry of populations from the steppe, but also that ancestry related to Ancient North Eurasians forms a major ancestral component of the populations of the present-day Caucasus25. Thus, both south-north and north-south genetic influence across the Caucasus is plausible."
Origin of Albanian is not in the Balkans. Just the opposite, origin could be somewhere between (Eastern) Anatolia-Southern Caucasus. Albanian has similarities with Armenian and (Ancient) Greek, even maybe some North Iranian languages? And how speakers of Albanian moved to the present Romania/Moldavia/Southern Ukraine (some Free Dacian tribes, probably Carpi, possible Costoboci), Albanian language had many different influences: Dacian/Thracian; Eastern Balkan Latin (from Romanian), German (Germanic tribe Bastarnae), Balto-Slavic etc. After coming to present day Albania language had influences from Greek, Slavic, etc, and after Islamization from Turkish (and Arab).
In this context we can look hypothesis that Proto-Albanian emerged somewhere around Eastern Black sea (for example todays Abkhazia and neighborhood). It is not much different from hypothesis that Proto-Albanian emerged in the area Anatolia-Southern Caucasus. Speakers of Proto-Albanian could go through Back sea area from Anatolia-Southern Caucasus.