The whole lack of using Gateways was idiocy from the start. Sure she doesn't want to have Aes Sedai fighting Aes Sedai and that's fair enough, but with the army she has rather then sit on the banks of the river, she could have quickly had them take the bridges and isolate the Tower guards, leaving the Aes Sedai trapped in the Tower unharmed, but her in command of the city.

Wooh. We have a big army. We won't use it though. I'm sure us sitting here not using it will be really, really scary though.

Still at the very least the rebels should be trying to organise safe passage of the cities inhabitants out of there. They remove any risk of collateral damage, and either the Tower agrees and leaves the rebels with an easier to take city or the disagree and the people know the Tower would rather see them starve. Win-win IMO. Add it to the list of stupid decisions. And the Tower would let every citizen of Tar Valon starve before the Aes Sedai skip a meal, in case anyone thinks packing them into Tar Valon would hasten the siege.