What I have learned so far is that many tutorials and courses focus on the API and the NoSQL development. However none of them are going to discuss much of the content on the handling local file types, handling SQL database. I think Node Read CSV File is a good to start with for playing with local disk files.
And also content like Node Connect to MySQL Database are essential for those who don't deal with trendy Nosql and APIs.
For interviews:
Lot of possibilities here. More you train yourself with the project the better for your exploration.
Problem is people follow typical trends for their choice of NoSQL and depending on external APIs with it. I think there is a lot to be explored with Node.