Who should control the Crimea and why?

If anything it would be the best if Crimea could be an independent country. However it was known that Crimea was given up by Russia when Soviet union has perished, and was given to the Republican of Ukraine. On the other hand, Russia now claims to be theirs and wants it back. Considering the specs of the government, gdp, and environment, Russia is more suited to take control of this country.