I would suggest to deploy it to production using different scenarios and approaches, and find out how this can affect your code.

I personally suggest that you can try websocket or socket.io to create real time application. If you have time much, you should try Graphql.

Try Loopback and Feathersjs

I think the standard ones are:

• Blog
• CMS
• Store

But I think it's important that you will work on something you are passionate about.