Information - In Defense
Miang is one of the most disliked characters in Xenogears fandom. Well, it certainly seems like nobody really cares about her, and a lot of people have negative opinions of her. It's to be expected, since she's... well... an antagonist. Even her creators don't seem to like her too much, considering how they described her character scent.
Though I don't make a habit of it, I like some dislikable characters. Miang is as complex as you want her to be, even moreso at times. You have to wonder exactly what's going on through her mind when she speaks her cryptic words, which can be taken in a number of ways.
I just get the sense that underneath it all, she doesn't like her situation, and is actually envious of Elly. Well, as envious as she could. After existing for hundreds and hundreds of years, it can get a bit tiring, don't you think? She wouldn't be to but help being a bit cranky. Also, watching over humanity for that long would make anyone not like them very much. I know I wouldn't. Just look at our current world. I'm surprised nobody got so fed up with it and tried to orchestrate a nuclear war to eliminate all of mankind already, with or without the intention of resurrecting Deus.
Simply put, Xenogears has plenty of deep and likeable characters, and I believe Miang to be one of them.