the 21st century continues on a more or less “business as usual” path, then having 200 million people (most of Ukraine + Belorussia + South Siberia) will be preferable to having 150 million due to the greater economies of scale and innovation that having more people enables.
Now to be sure, Russia can survive without the Ukraine as a declining Medium Power.
Even so, “population is power“, as a powerful commentator keeps reminding us in this very blog.
And all that is apart from the basic principle of reuniting a separated people, promoted by all Russian nationalists from Ilyin to Solzhenitsyn, and repairing the standing insult to the aesthetics of the world map represented by fake and gay countries such as Belarus and the Ukraine.
“Winning hearts and minds,” , is unfeasible anyway; even going so far as giving back Crimea will not restore goodwill and invite only contempt.
Reunification through Eurasian integration was permanently ruled out in February 2014, when a false flag-abetted coup unseated the bandit President Yanukovych and brought Maidanists to power.
Reunification through military means was ruled out – probably permanently – in May 2014, when Putin recognized Poroshenko as the legitimately elected President of the Ukraine. While certain nationalists, including on this blog, still entertain fantasies about invading the Ukraine and ruling it like a Reichskommissariat, that would be worse than just immoral – it would almost certainly fail, since it buys into the narrative that Ukrainians can only become Russians at the point of a gun. “There is no compulsion in religion”, as the Muslims say.
Finally, given the collapse in “Russophile” attitudes in the Ukraine after 2014, there is no scope today either for “deals” with new “partners” like Tymoshenko. Which even on the off chance that they happen will only degenerate into the usual post-sovok traditions of stealing money from some project, which always, and not undeservedly, only feeds foreign disdain for Russia.