Golbez - As much as I love FFIV they REALLY overused the mind-control gimmick and I found that more frustrating than anything else. He was still a decent villain though.

Though I will concede for the most part. I was arguing at roughly 4am, so I wasn't really making the best points. Though that doesnt mean I'm done here.

Vayne actually made some pretty interesting speeches, and especially his first one in dalmasca doesn't even paint him like a bad guy at all.
Final Fantasy XII - Vayne Solidor Speech - YouTube

And here's a great video showing the 3 main "villains" Cid vayne and venat who I'm really starting to see as the real villain. It's been a long time since I've played FFXII, so I apologize.
Final Fantasy 12 - Vayne Meets Venat - YouTube

Here's a scene with vayne and the emperor
Final Fantasy 12 - Vayne And The Emperor Gramis - YouTube

Here's one where the judges talk about vayne, and some pretty interesting backstory is revealed.
Final Fantasy 12 - The Judges - YouTube

Vayne isn't really shown as a serious badguy until you hear some backstory and analyze his character a bit. He forgoes many common villainous tropes (though he does still have others) and becomes something great in my opinion.
I still really enjoyed vayne, and I find him to be quite a deep character.