Sadly, I believe Putin has the same delusions of grandeur. If he is successful at taking over Ukraine with only Western financial repercussions, his government will only become more authoritarian and his repression of dissent even more barbaric. If he didn’t hesitate to poison with radiation his perceived enemies in foreign countries (and got away with it) before, imagine how free he will feel attacking other countries Internet infrastructure (which they have been working on for decades) with little to lose.

To a great extent, yes. Stalin didn't care for human life, killing any who disagreed with him, and condemning millions to a miserable death in the freezing salt mines.
Putin has a similar mentality.

No I don't think so, Stalin was cynical and realistic to a criminal degree, where Putin is delusional, and almost certainly half believes his vision of his destiny.

I think he wants to be, reuniting the Soviet Union is his stated goal and he expects to rule with an iron fist. He's delusional and hope he'll be able to deal with it when he fails but the ability to face reality is lacking in many world leaders.