Why didn't Cadsuane have the Greens leading the fighting? Merise is considerably older and more experienced than even Verin, so to have your strongest and presumably most battle ready Channeler on the sidelines along with her pet Asha'man and two Warders seems like a massive wasted resource IMO.
I would have had Merise and Narishma in the field linked with Beldeine and had Daigian, Hopwill and Elza manning Callandor and had Nesune and Erian (level 17) in a link to protect the "civilians". Having an unlinked Erian was just a waste really, even linked with only Nesune they would have been strong enough to at least slow a top-tier channeler down, but on her own Erian would have been swatted aside with ease.
Daigian and Hopwill along with Elza would have been an adequate circle for the hilltop and with Callandor it wouldn't have made much difference regardless. If she was really worried about how strong that circle needed to be she had 2 spare Aes Sedai just hanging around doing nothing. Hell, given Callandor's power she should have had Nesune link with Elza and Erian and go out as part of the protective ring. Those three would have been roughly the same as she knew Verin's circle to be and losing Elza from the Callandor circle would only have meant Hopwill would have needed to meld the flows, given his battle experience he probably would have done as well as Elza did. But given Aes Sedai nature I can't necessarily say I am surprised by her wanting a woman to run the circle and there is the flaw in Callandor she was already aware of so I suppose that's a forgivable decision. But it would have been smarter to have Daigian, Eben and Elza manning Callandor and sending Merise and Narishma out with Beldein and/or Erian.