Yes I have her in a red white green deck for the mana fixing. But my problem is balance. Either i get too much mana and no playable cards or I get cards and all the mana seems to magically sink to the bottom of the deck when I need it. Right now I'm pitting it against my mid aggro vamp deck. This deck just can't handle a faster deck. I need to get these cards out in four turns and that's hard. I need a perfect hand to pull it off and I never get the cards I need at the top of my library. So yeah avacyn sucks because of her high mana cost. I had one perfect hand that won one time. So far though the vamp deck is a win.
Yes I have a pure white deck with one of her. Sam hates it. It's a stall deck with lots of removal and stall cards. It usually works but I find that with out being hex proof angel of avacyn just gets killed right away or cancelled and other horrors that my sisters deck contains. There are no white cards that can make her hex proof to my knowledge. I'd even play older cards because this is a casual deck I'd never be stupid enough to go pro with it. I know it suck I"m not stupid. But I'm not familiar with old cards as you are. I came exactly as ravnica came out.
I'll be looking up some of those cards you mentioned.