The Hall can still provide a check and balance on Egwene's power. She didn't take anything fundamental away from them in how they function or pass laws. If anything, this is a much needed check on the Hall's power, preventing them from shutting out Egwene or other Sitters, even an entire Ajah - as was done in Elaida's coup (and most likely in other instances in the past).

All Egwene's motion did was involve more voices in the discussion of Tower Law. Voices that could potentially disagree with her own views. She is still outnumbered by them and can only "bully" them if they allow it.

Her move dispels the secrecy involved in Aes Sedai politics - one of their biggest fallings and a major criticism that comes from characters in the story as well as readers. Now the Aes Sedai will have to think twice before manipulating the Hall for their own personal interests.

This new law also means Egwene can't push things through the Hall without having everyone present to either agree or disagree with her.

It may take some time, but this change in Tower Law has the potential to begin to actually change the way Aes Sedai live and interact with the world. Remove the manipulations and secrecy from their politics, thus forcing them to approach these issues from a different perspective, and eventually that will leak into the way they approach the world at large.

I would think that the biggest Aes Sedai detractors would cheer at this moment and the potential ramifications that it holds for the future of the Aes Sedai's role in the world, perhaps a small step towards becoming Servants again.