I totally agree with you, and I think that the approach shown in yesterday's Livestream is much more on point for the concept.

Concerning Shalice iconic movements I got the idea that she could only be seen as a reflection in mirrors throughout the game, since she is going to be the final boss Alice does not interact with her at all. In those reflections Shalice would try to teach Alice to defend herself, Shalice would display the weapons Alice could use or how to weaponize elements on the environment in hopes Alice gets stronger, strong enough to beat her Shadow and be ready to accept her and face reality. The habitants of Wonderland are aware of Shalice's presence and will try to preserve Alice intact or attack her thinking she is the Shadow, this would explain why Alice will have to overcome trials deviced by each of them. In the end Alice won't be prepared to stand toe-to-toe with Shalice and, as American suggested, Shalice traps Alice in a cage and takes the basic dress for herself, making the simbols in the apron along with the necklace change into the ones seen in AMA. This is just an idea, Shalice could be seen in the background sometimes like a guardian for Alice, off course she would not be aware of that.