I think the most likely is Crimea gaining full autonomy, and quietly realigning with Ukraine on many issues while being vocally pro-Russian.

Seems like Putin, or at least his proxies have overplayed their hand. While Ukraine objects loudly to infractions against their sovereignty, at the end of the day realpolitik should set in and prevent bloodshed. Because dropping large segments of ethnic Russians from the voter rolls will help ensure Ukraine's real independence in the long run.

The Tatars are an interesting problem, but if Crimea does not have to implement Russian decrees and a local govt is smart enough to not cause problems.. I wonder if they would object to independence. I dont know the answer, and suspect it revolves around a great many local circumstances of which I am unaware.

For who could be free when every other man's humour might domineer over him? - John Locke (2nd Treatise, sect 57)