Vader gave me slave vibes. He couldn't best the Emperor his own so he was Broken man with nothing left until he found out he had a son. Then offered team up of millennia.
Emperor was space Hitler.
He's aesthetically cool. Deep imposing voice, sick armor, nonchalantly wields his lightsaber one handed (which screams "I'm better at this than you"), strong enough with the Force to pull down an AT-AT.