Good choice with Honey Bun.
I Have Confidence might work, but I wouldn't go with Amazing Mayzie. The character Mayzie is big and outgoing like Winnfired, but she's a lot less modest and shy. (hahah yeah Winnifred's shy..
If you're going for Aggravaine, maybe you could try Stepsisters' Lamet, because Aggravaine is bratty in that respect. Another one that might be good would be How Lovely to be a Women from Bye Bye Birdie
I know Kim and Aggravaine are completely different characters, but that's kind of a vain song and Aggravaine is deffinately vain.
Hope it helps!