I ordered the book it is good to understand about microservices, but programming is not perusal, it is hard to understand how to create system and use tools if we don't see it. So If you realy want to teach how to create systems with seneca, create some video courses with Udemy or some other video streaming site.

Improvements:

• Implement login system roles and premissions
• Add pagination somewhere
• Upload files
• Create self relationions
• Multiple services with differnet kind of databses
• How to deploy it to porduction
  ...

This are not hard things to implement with monolithics but can be tricky with microservices.