I don't think Obama would be too bad to have a beer with.
Kim Jong Un. We could talk about basketball and I could probably piss him off by playing downloaded copies of the Adventures of Kim Jong Un (starting with the story of how he took back his swag from Psy).
Vlad the Impaler?
The guy killed traitors and turkish people, nothing wrong about that.
Impaling was a slow and painful death, probably worse than crucifixion.
http://www.vladtheimpaler.info/the_impalement.html
That is pretty monstrous, but for his time, no, hes not that incredibly bad.
Joseph Stalin, to tell him that he did good job putting the capitalists, thieves, parasites and leechers where they belong, under the ground.
People who belong to those categories are worth less than a dog shit on the grass. So he did a good job by removing them from the society, ofc before they died of hunger, cold (Siberia) and abuse they did some useful work in mines, quarries, lumber mills, he was a wise man.
Putin, so I could slit his throat with the bottle cap from my beer.