It's not just Moscow that has economic obstacles affecting a rational outcome in Crimea. From the National Interest:

The reforms would allow Ukraine to borrow approximately 60 percent more (from $1 billion to $1.6 billion) from the IMF’s emergency fund. That’s money that Ukraine can use to pay off its debts and avoid a default. In certain scenarios, the IMF makes exceptions and allows countries to access additional funds, as it did with Greece and Ireland after the financial crisis. But there’s no guarantee it would do so with Ukraine. By blocking the passage of the IMF reforms, Republicans are actively making it harder for Ukraine to pay back its loans.

...

“The rest of the world is furious at us,” Ted Truman, a senior fellow at the Peterson Institute for International Economics and the assistant secretary of the U.S. Treasury for International Affairs from 1998 to 2001, said. “For us to say, ‘We just stiffed you in January’ and now we’re turning around to try to ask you to be part of the team helping Ukraine, we look silly.”

“It does undermine our credibility and leadership,” he added. “We look like we’re giving with our right hand and taking with our left hand.”
Of course, there's also the risk that any aid to Ukraine will be stolen anyway:

As always, it’s about preventing a default during which bondholders and lenders, including numerous Western banks, hedge funds, and other speculators, would finally feel the teeth of a free market and be forced to take losses, big losses, perhaps big enough to sink a lender or two, which would be a welcome sign of housecleaning by market forces. But that won’t be allowed to happen. Instead, taxpayers in other countries will be shanghaied into bailing out these bondholders and lenders, but indirectly, under the guise of bailing out the Ukrainian people.

...

But Danilishin’s idea that aid cannot save the Ukrainian economy because the money will simply be siphoned off by pandemic corruption, and that instead the state should go after the oligarchs who plundered the country? It “can’t be implemented because the ‘revolution’ in Kiev has been partially sponsored by the oligarchs who will not let the state become stronger,” Mândrăşescu explained.
From an economic point of view, the revolution in Kiev did Ukraine no favors. In fact, it may have sacrificed whatever remaining stability the Ukrainian economy had. But I suppose Ukraine's territory integrity (there is a vote for Crimean secession planned this month) is a small price to pay to bring the Washington Concensus to Russia's doorstep.

On another subject, DNI made a statement to the effect that they were not "caught off guard" by the Russian intervention because the "decision [to intervene] was made at the last minute". With an open territorial dispute between Ukraine and Moscow (not to mention Russian troops in Crimea), I think the prospects of Ukraine ever entering NATO are at an all-time low. We'll have to wait and see what IMF reforms are proposed and if that's politically feasibility for the new government in Kiev.