The point was to take away her mixup on block game. They changed her play style, same as they did for the other top tiers. She now has to play very careful keep away, sort of like Dizzy. All the top tiers (and Noel for some reason) got playstyle changes.
Nu as a rush down apprentally (though that seems odd to me)
don't even know about Arakune, just that he's different
Noel a Grappler.
and Rachel as a keep away.
You can't judge how good they are until you see their matchups, which we don't know yet. If they had made small changes to their design and didn't change their playstyle, then you could easily make assumptions based on matchups. People thought Jin in CT was awful until they figured out BnB, and now he may be one of the best. Just have some patience man, wait till you get your hands on her ittie bittie *******, learn the new Keep Away style, and then make a judge if she's viable or not.