Putin is pretty good. He kills his rivals, and even reporters that don't fall in line, with al most no repercussions from his own people or the international community.
By that measure Hitler qualifies. Any leader driving his country over a cliff as Putin is doesn't make it.
I don't think Putin is one of the greatest leaders of all time, but he isn't driving Russia of a cliff. He plays the international community like a deck of cards. He is a master poker player, so much so that no one calls his bluffs.
He keeps placing bets that he can't win if called and backing himself and Russia into a corner. He is bankrupting the country on a house of cards.