Initial reaction after my first partial read of “Worlds in Peril” and skim of the rest:
Solid mechanics, great artwork, and many explanations. In fact, the mechanics are better than i assumed based on YouTube videos of gameplay, as I think they got one or two rules wrong. Bravo on the artwork, game and generosity of explaining PbtA principles!
The weaknesses appear to mainly be the organization of the text, and a needless reliance on a complex vocabulary.
I work as a newspaper journalist, and the vocabulary makes me cringe because it is clearly outside of the range of an average reader. I think that unnecessarily limits the potential audience of the game, which is a shame. For the widest readership, your safest bet is to aim mostly for a 6th-7th grade vocabulary with a minority of more complex words and concepts.
A good rule of thumb that writers for older children use is to minimize the use of words longer than two syllables. You don’t have to outlaw such words in your writing, but make them exceptions. That limitation forces one to downshift one’s word choice.
You may also want to avoid abstract concepts such as “agency” and such in explaining game rules. Or better yet, use simpler terms to express the same idea. Rather than “agency,” you can talk about when player’s actions still matter in the story.
The game’s authors are intelligent adults. Don’t require game players to be so. Some are but not all.
Overall verdict: Good game 🙂