There are really two stages to the current Ukrainian crisis. The first stage is already well underway - the annexation of the Crimea. Russian already controls the Crimea militarily, and no doubt the upcoming referendum will be solidly in favor of returning to Russia. First of all, the majority of Crimean inhabitants these days are Russian, bolstered by the mass of Russian troops that have just be sent there. And if that isn't enough to get a majority, Moscow is talented at stuffing ballot boxes, as the 2012 presidential election of Vladimir Putin showed.
On the other hand, the Crimea has been a part of Russia since the 1700s. Khrushchev transferred it to the Ukraine in 1954, never thinking that the Ukraine wouldn't be an integral part of Russia forever. It is the port for the Russian Black Sea fleet, so naturally the Russians are upset at the possibility of losing it. Although their approach has been heavy-handed, there is certainly reasonable precedent for Russia's claim to the Crimea, and no doubt they will end up with it again, whatever the West does or says..
The second act has to do with the rest of the Ukraine. It is important to understand that although the Ukraine is in fact a separate country, Russians have always considered it part of Russia. Going to the Ukraine for them is like going to California or Arizona for us. And losing the Ukraine to the West is for them more or less like California leaving the US and joining an alliance with Russia would be for us. Russia is paranoid about invasions from the West (for good reason - think of Napoleon and Hitler in recent times) and has always wanted a series of friendly buffer states on its western borders. So to lose control of the Ukraine is a very, very big setback for them, and they will not let it go lightly.
So the second shoe we are waiting for is whatever Russia decides to do about the rest of the Ukraine. At the very least they will engage in a long-term effort to regain political control of the Ukraine, and once again put into power a Moscow-friendly government. They might decide to foment unrest in the more Russian-populated eastern provinces, and then invade to "protect" Russian citizens. We will have to wait and see - but they will surely try to do something to regain control of the rest of the Ukraine - it is a high priority for them.
In fact the "Westernization" of the Ukraine would be a good thing for Russia in the long term, though a bad thing for the current power elite, because it might eventually help to bring real reform to the Russian system. But "westernizing" it won't be easy. The Ukraine suffers from the same endemic corruption that infects Russia. The government that took over after the "Orange Revolution" of 2004-2005 was just as corrupt as the Soviet establishment it replaced. Kleptocracies like this are hard to reverse, because the corruption gets embedded deeply in the whole culture. - it is simply "the way things are done".
So it will be interesting to see how this second act plays out, and how effectively the West can counter it. I expect that Putin is relying on the notoriously short attention span of the West, and Western greed, to limit the effectiveness of whatever sanctions we might attempt, and he may be accurate in that assessment. We will have to see.