Rose Mcgowan as Glory is kinda weird. I don't see her as a Goddess.
Well, I didn't see Claire Kramer as a deity anyway. My first two choices were Jennifer Aniston and Heather Locklear, but Jennifer's going to be busy with Friends, and Heather had a pretty busy film career OTL even during the run of Melrose Place; it could only get busier. I simply can't see either of them wanting to do it in 1994.
With Rose McGowan, the only thing she had done up to this point would be Encino Man. Her first real big break was Going All The Way in 1997, followed by Jawbreaker in 1999. And her OTL career shows her to be very willing to due "genre" material.
Same with Jolene Blallock. Merry, innocent sister?
My first two candidates were Mercedes MacNab and Christina Ricci. However the former looked a little too much like a younger clone of Kristy at the time, (Dawn is meant by the monks to be Buffy's sister, not her exact dulicate) and the latter was already off to a roaring start to her movie career.
Holly Marie Combs as Faith... Awesomeness.
Same for Angelina Jolie as Drusilla. Would love to see that.
In the relevant timeframes, they were young, hungry, and looking for work.
My original choice for Faith was Alyssa Milano, (It would have been basically what Samantha would have been like if Tony had been killed when she was seven or eight in a mistaken mob hit, and raised by a hooker of a mother) but Who's the Boss?'s final season would have gotten in the way.
My original choice for Drusilla was Winona Rider, but from what I can see her most regular TV role ever OTL was The Simpsons.
BTW, by first three choices for Joyce were Susan Saint James, Sandy Duncan, and Holly Hunter. But Susan at the time was fed up with being a TV mom, Sandy was still busy with Valerie's Family, and the only time Holly Hunter does anything TV related is if she's also involved in the production side of things.