I was going to answer this on many levels, but decided both both brevity - and to keep my powder dry, so to speak - to limit it one, that being the question of autonomy.
South Ossetia is not seeking independence, or even independence after merger with North Ossetia (it would be unviable in either case). Rather Russia, after unilaterally issuing passports to some of the inhabitants, is claiming Ossetia as it's aown and that it be absorbed back into the Motherland.
This is a claim that, since the early 1990s, has not been accepted by one single other country in the world, mainly because of the precedent it would set. Independence of a small state is one thing, but a land grab by another based on the ethnic origins of the inhabitants? Do you have any idea of the number of equivalent situations this could inflame and the wars that could ensue?
In the Caucasus and Eastern Europe Russia would claim at least the Crimea, if not the whole of The Ukraine (their Foreign Minister obliquely did so yesterday); they could claim at least 30-40 of each of Lithuania, Latvia & Estonia, and large chunks of the various 'Stans besides.
But elsewhere it could set an even more dangerous precedent. Pakistan would have a far, far, better case to Kashmir; China to Taiwan and large chunks of Vietnam and other neighbouring states. In all there are over 129 territorial disputes based on ethnic issues ( Standing your Ground: Territorial Disputes and International Conflict by Paul K. Huth).
Internally in Europe you would reopen issues between Poland, Hungary and Germany plus France and Germany over the Alsace etc. (have a look at the border changes during the 20th Century).
Not only does the claim have no accepted precedent, it is far too dangerous to let stand.