The layout is overall nice and reads really well.

Only feedback I have on that is-

If possible, a small text or icon reminder on the tabs would make them even easier to flip through. Though its beyond cool to simply have them at all in a smaller book like this.

The other is when soloing the world table and oracle rules are going to get referenced at first, a lot. Often enough to make hunting it down in the middle of a section kind of awkward.

It would be nice if it was at the start, or end of one.