Pretty good! The content itself meets your goals and the reader's expectations (in my opinion anyway).

Here are some critiques:

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I think you should link to some information about the programming patterns you mention. I hadn't heard of any programming patters (besides OOP) prior to watching your videos on them.

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I don't know if you can actually do anything about it, but having one side of the page be blank is kind of weird. Page 17 is very jarring since it's a tiny picture and then a lot of blank.

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I don't know if you can do anything about this, but the white is very bright and hurts my eyes to look at.

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There are small inconsistency concerning how you do page breaks.

Page 17 could have had the "Pro/Cons" dialogue but you decided not to. This allowed you to out everything on page 18, but page 34 you did decide to put the pros and cons dialogue on there which splits up the pros and cons section.

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You're also really inconsistent about the Title of the pros and cons section:

Recipe #1: Pros/Cons of a Spawner2D

Recipe #2: Pros/cons of an EventPlayer (note that con is lower case here)

Recipe #3: Pros vs cons of a SceneTransition (weird use of "vs")

Recipe #4: Pros and cons of a PauseMenu (switched "vs" with "and")

Recipe #5: Pros/Cons of a BackgroundMusic (Also the header for Recipe #5 is written as "Recipe # 5" with a space after the pound symbol)

Recipe #6: Pros/Cons of an ActionHandler

Recipe #7: Pros/cons of a ShakingCamera2D (another lowercase "cons")

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In the "How does the book work?" section, you say the following:

"On each recipe, you will see concrete use cases where I used
them. You will also find how to setup the SceneTree,
secondary resources, and the script. It’s really meant to be
straight forward so you can quickly consult it whenever you
need."

This seems to imply that each section should be self contained. That makes it a bit awkward to read some sections like Recipe #4 where the first paragraph is:

"That said, a PauseMenu is a Node that handles the SceneTree pause states."

Which doesn't make any sense unless you've previously had read Recipe #3.

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