The vast majority of Russia is so cold that a huge percentage -- roughly one half -- of all energy expenditures is wasted on heating. Instead of using energy to produce goods and services to improve the quality of life, Russians use it just to keep warm.
With few exceptions, heat is generated through the combustion of fossil fuels. Before fossil fuels had become widely available, Russia was a miserable place to live for all but the 5% of society who were aristocracy and government workers. Russian peasants across most of Russia lived in abject poverty, barely able to scrape by in the harsh climate and poor agricultural conditions.
This was not because the country lacked democracy and a free market economy, but because the climate didn't allow people living on the land to build up surpluses and engage in trade and other nonessential activities.
Today, the cost of heating and maintaining infrastructure over enormous distances puts added costs onto many goods and services -- for instance, transportation. Train travel in Russia is 2 to 3 times more expensive than in Ukraine. And yet, except for a few cities in European Russia, people are just as poor as in Ukraine (or poorer).
Many people in the outskirts are effectively stuck where they are, unable to travel further than an occasional short trip by train to the nearest city. Some visas for international travel can only be obtained at consulates and embassies located in Moscow or St. Petersburg, which are a prohibitively expensive trip away. Flights are expensive, and train travel is expensive and takes forever.
Without fossil fuels and other natural resources to exploit, most of Russia would suffer a catastrophic loss in standard of living. As global temperatures rise, primarily affecting arctic regions, Russia stands to gain a lot of effective territory and be able to spend less energy trying to keep things warm and liveable for its inhabitants. Global Warming is good news for Russia.
In Ukraine life was never so hard. The comparatively cold, continental climate kept European-like urban development from occuring over much of the country. Most people lived as peasants with too little surplus to allow for the creation of large towns. But life in the countryside was rarely so difficult -- thanks to a warmer climate and better soils -- that people and livestock were constantly on the verge of starving to death and had no time to do anything other than subsistence agriculture.
With train travel comparatively inexpensive and southern lands quite close, Ukrainians can more easily take vacations to places like Crimea, Bulgaria, and Croatia, which are all a day's trip away. Europe with its culture and history is just a stone's throw away, and many Ukrainians have been to Poland at the very least, if not further west.
Ukraine is also dependent upon coal and gas for heating. But if these were taken away, people would have a place to go -- back to the countryside. Wood might soon be in short supply, but cold spells are shorter and less severe, and the warm growing season quite a bit longer, than in most of Russia.
From a climatic and geographical standpoint, the most favorable areas in Ukraine for living are probably Transcarpathia, Galicia, and Bukovina -- all in western Ukraine, which has a milder and somewhat moister climate. It's no surprise that these areas developed an urban culture similar to that of central Europe.
To these we might add the Crimean foothills and coast -- another area with quite a bit of development historically, though little connected with far western Ukraine.
Even sandy, chilly Kiev is in a better location with better climate specs than the Russian capital, Moscow, although still somewhat cut off from the civilized world.
By choosing Ukraine (if one has a choice at all), your putting your bets with a place that, for geographical and climatic reasons, historically has tended to have a better standard of living than Russia.