Elaida ended up in Egwene's shoes back in TGH while Egwene was officially raised to Elaida's position and immediately started to undo everything Elaida had done.

Then Elaida gave the Seanchan Traveling... which, beside unwittingly putting the Tower in such a state it could accept Egwene as Amyrlin and also keeping Mesaana and Alviarin/BA entertained and busy until they could be dealt with, was Elaida's contribution to the LB. She likely sat it out otherwise, a complete nobody instead of the woman who would go down in History as winning the LB she daydreamed to be, the arrogant moron.

The Seanchan had determined out the sisters were useless in battle, but they didn't seem to know against Shadospawn/DF it would work. We haven't seen any of the AS damane in TG, IRRC. But it was a fitting end to the character that her role in TG was 100% anonymous anyway.

She didn't even see Elayne becoming Commander of the Light, but we know she would have misinterpreted that again as the meaning of her first Foretelling.

I guess RJ planned no more, it's perfectly adequate resolution, but would have brought Suffa back during the outriggers. Brandon seems aware that Suffa survived TG, it suggests RJ's notes made that plain she had to.

Don't forget it would have looked more like proper resolution of the arc had AMOL been one book. Elaida would have met her fate 2/3 into the book, when all the pre-TG resolution came together with Mesaana's downfall, the Verin reveal, Moiraine's return, the Hammer, etc. It's the book split and Brandon's "inflation" of the finale that gave Elaida's fate a little smell of a "loose end" gone too early from the story that it isn't, really.