With her new baby, I'm rather shocked that Heather wants to play super-hero or that Mac would let her.
In AF v4 (or whatever, the next one) I'd like to see the Hudsons retire to raise their family. I can't really see anyone donning their suit(s). Maybe Walter if he ever lost his powers? Or maybe even Mapleleaf?
As for Elizabeth's power-level, I've always assumed that she lost much of her power once the Socerer was defeated. After all, thats what she beacame Talisman to do.
I still think she's as powerful as Shaman though.