That is the same analysis that I have heard - the Russians only want the heavy industrial areas in the southeast, linking them to the Black Sea and Crimea, where they have lots of ethnic Russians - Luhansk and Donetsk.
The poorer agricultural areas in the West with a higher percentage of Ukrainian speakers, are more of a charity case whose bills they would rather foist onto the West.
It really depends on the government. Ukraine's previous leaders have been Putin clones, competence- and ethics-wise, except Ukraine isn't, unlike Russia, the Saudi Arabia of the north, vis-a-vis natural resources. South Korea was the agrarian part of Korea, yet grew to dwarf its northern counterpart. It comes down to leadership. Ukraine doesn't need a genius to take the reins - someone like any of Central Europe's leaders will do.