Jack of Blades
Handsome Jack
Definitly Kreia from Knights of the Old Republic 2!
There is a thin line between not knowing and not caring, and I like to think that I walk that line every day.
See, Kreia rates high, but for me loses points because of how sanctimonious she is and how much of a mouthpiece Avellone made of her. It's common with the characters he writes, but nowhere is his writer's pet effect on display more than with Kreia, whom the player can basically never disagree with without sounding stupid.
To me Delita is more of an antihero than a villain to be honest. He didn't kill anyone for cold blood for nothing he did it for the good of the world and the country. His methods are indeed questionable for sure because he is driven by revenge specially against the nobles he is still holding grudge against them because of being common born and not from the nobles like Ramza or Zalbag. After the ending scene it says that he ruled Ivalice justly and was praise by the people of Ivalice overall (with the exception of the people he used and their relatives of course).
The definition of anti hero to me is the one who has the same goals as the hero (the greater good for the world or whatever) but his methods are not white knight noble and sometimes very questionable methods to reach that same noble goal.
I favour antagonists - especially if tragic - over outright villains, so here's some of my favourites:
Gabranth from FFXII
Rufus Shinra from FFVII
Priestess Selene from Grandia II
Yotsuyu from FFXIV
Regula van Hydrus from FFXIV
Sydney from Vagrant Story