While undoubtedly a great game with tons of fresh ideas for the formula, I still feel like this was a step down in respect to It Takes Two. For one, the worlds that we see brought to life in the story don't feel like they were lifted from books at all. They barely feel like videogame worlds at best.
Take Mio's story about the robots enslaving the giant Kraken creature: what would the plot of that story be, as a book? I assume we are taking control of the main character of the story, but there are no other characters there. Maybe a secondary protagonist, sure, but no antagonists, no supporting characters, nothing. At best, this could be a very short story.
Or take Zoe's story about dragons: same problem, there are no characters besides the supposed protagonists, the dragon antagonists and his minions - all of which could barely be classified as such. The baby dragons themselves, while very cute, are also barely characters and their actions in the story, which we are supposed to be playing from the beginning to the conclusion, amount to physically doing things and going to places.
Compare this with It Takes two, where a lot of the bigger areas had goofy, full mini stories or at the very least interesting settings with characters that meaningfully interacted with the protagonists.
It even sometimes feel difficult to discern what kind of story could have been written with these - as in, what would a writer, realistically, even be describing here?
To me, this feels like a huge missed opportunity, since "travelling through book worlds" is such a good pitch.
Another missed opportunity is how generic these feel. Since they were trying for a more serious story and a clear dichotomy between fantasy and science fiction, we almost exclusively get very generic settings, save for the mini worlds in between them. These are also much longer, leading to less variety.
All and all, still a great game, I just hope that these design and story decisions aren't here to stay for the next chapter in the series.
