To what extent did Russian rulers modernise during the period 1855-1964?

During the period 1855-1964, all Russian rulers attempted to modernise the country economically and in instances, politically, but not at the expense of losing control over the populace. The failure of Alexander III to politically modernise as evidenced through the rejection of the Loris Melikov proposals pales in comparison to the failure of Nicholas II through the rejection of Industrial Committees which sabotaged the longterm war effort. Stalin and Lenin modernised the economy marginally. The NEP of Lenin which moved away from forced grain acquisitions and the introduction of a farmers tax and increased output and living standards was undoubtedly successful, but represented a progressive policy rather than a form of modernisation. Stalin pursued an especially active approach through successive five year plans. The end result of these was the system of collectivisation and vast construction projects such as the Dnieper Dam and the city of Magnitogorsk. The most willing and successful rulers in terms of modernising the country were Alexander II and Khrushchev. Alexander II vitally modernised society through the abolition of serfdom which could revolutionise the rural economy, Khrushchev increased agricultural output by over 50% of the 1953 harvest through the Virgin Lands scheme and transformed the economy into one focused on increasing domestic living standards through the focus on consumer goods and the doubling of the housing stock.
However the modernisation aims of Russian rules clearly were not all the same, indeed Nicholas II actively avoided modernisation. Lenin and Stalin were motivated to pursue modernisation in order to increase the control the 'party' exerted over the state. Alexander II and Khrushchev both had the most altruistic motivations to modernise, yet it can be argued that Khrushchev aimed to increase personal power and it could be argued that the positives which emerged from his pursuit of modernisation were mere fortunate byproducts of his real intention to increase his own power over the state.