Most of the Aes Sedai were already neutralized by Rand when he got out of his box. Yes, the Saido had some wise ones who could channel, but none of them had experience in dealing with male channelers once the Ashaman had taken the field. Therefore they were completely inept and a non factor.

If anything the Wheel of Time has taught us, A channeler is worth more than a 1000 troops. Aiel army vs Ashaman = lot's of aiel blood on the floor.

The Ashaman are a force to be reckon with, but it's huge mistake underestimating the Seanchan war machine. After all, they fought Rand and his Ashaman (many of which included Taim's very best trained henchmen) to a stalemate in Altara. Alivia is just one example, she's been trained in the most destructive and dangerous weaves, and is even stronger in power then Nyneave. Who knows how many more Damane like Alivia the Seanchan still have collared. The fact that they have so many Damane at their disposal is scary enough.