A) Maire tried antimagic field with the RW as I remember and it didn't work. Additionally, his magic WORKS in antimagic fields.
Does it? I thought I recalled him having to drop the field in order to turn into the Wind and do spells and such. He kind of had a very flexible tactical situation. He could zip around as the wind to get close to casters, then appear, activate his field, and beat the crap out of them with monk-ery, and when the casters had been hammered out, he could drop the field again and unleash magics on the fighters without opposition.
Nonetheless, he is still VERY evil and VERY dangerous.
Hells, yes. I consider him MORE dangerous than the Eyeless One. Let's think back - of the two of them, which one got an axe buried in his head and wound up trapped in an unbreakable godly prison, and which one beat the snot out of every regent that came up against him, completed his plans to perfection, and laughed himself sick at the other's predicament?
The Eyeless One assumed his plans would work. The Red Wind brought multiple redundant ritual aides/components and had detailed plans for how to deal with every setback we managed to deal him. He's a powerful, intelligent, ancient villain who's read the Evil Overlord's Guide. I FEAR people like that.