In terms of pacing, this continues to be one of the stranger adaptations of the year.
Alis' mention of his plans to "save the world by destroying it". In order to try and explain this to Ai he frames it in terms of a classic philosophical treatise - that there are two worlds, not one. There are many different flavors of this idea but he presents it in simplest possible terms (probably best considering his audience, Ai) - that there's a "real" world which will exist even when mankind is gone, and a world that exists only as our perception. Ai, to her credit, picks up on the nut of this concept - it means that everyone is living in a unique world, defined by their own perception. That might just be a bit of a theme with the Gora students and their various peculiarities, and it seems very likely that Alis' plans are going to be part of what comes next. Perhaps the most direct explanation is correct, that he plans to save the only true world as he sees it, the objective one that exists beyond human perception, by taking humans out of the equation. That at least could be an interesting development born of this arc, and there's also a last-minute development to deal with, in that Yuri has apparently left Scar behind (whatever that means).