So, ineffectual saturday morning cartoon villainy, rather than actual villainy?
Honestly, if you want to play the bad guy, you're better off not 'playing'. DM. Run the game. Then you get to play the villain. Not just 'a' villain, THE villain. The one making the heroes react. The big bad guy, the threat to the world, the one who gets the huge armies and who discards game balance and even rules-as-written in favour of drama.
Hell, take Skeletor as an example. Big evil guy, minions. No players would agree to be mere minions, and it would break down in OOC bickering instead of IC plotting and scheming.
The Masters of the Universe are all equal. They have no rank, they have no authority over each other, and they debate things even as they happen. They're the PCs. They're the Good Guys. They play by the rules because they're Good.
Evil campaigns don't work because evil requires a grand vision. Hitler would not have been a threat if he was instead four guys constantly bickering and trying to one-up each other. He was one man with a grand vision, an ideology, and a war machine to back it up.
This. Saturday morning villains are petty and vain to a fucking fault. Over-the-top evil. Don't pluck the baby from it's mother's arms, kill it, and then rape it and the mother. That's just brutality. No, true evil is plucking the baby from it's mother's arms, stealing it's bottle, making it cry, handing it back to the mother, and then emptying the bottle over the mother's head and laughing in her face. Why is that more evil? Because you can do it again. Stalk her, do it every day for a month until she's a nervous quivering wreck and the baby is terrified of you. Then one day you just... Don't. You walk on by. You don't show up. Life returns to normal.
This works too. The plotting, scheming minions, the generals at each other's throats, the lackeys played off against each other so as not to gain too much individual power and threaten the villain.