Hi @justinyao04,
Thanks for reaching out. I think your initial question of Code Walkthough vs. CodeTour may have already been covered in this post and this one.
For your question about the extent of the swift book, the swift book was only a suggestion to get started. I think it would be good to cover more hands on examples that at least cover the basics, since VS Code allows you to run, compile and debug examples which you can't do directly on the book. Having an extensible way to show the examples would be beneficial because even if you don't have the time to implement all examples, someone else can add to it later or modify them as the language evolves.
Hope this helps!