What technologies do you need to add to those already studied in order to be considered a web full stack developer?

Question

ASP.NET

Good day!
Please help me fill in the gaps in my technology stack for developing small and medium web applications. In the specifics of the current place of work, I am tied to ASP.NET, but this is not even bad. Now I more or less know the following: C#, ASP.NET MVC, MS SQL Server, HTML/XSLT, CSS, JS. In addition, I study Entity Framework, SignalR, and dependency injection (DI). But I still feel like something is missing. Now I'm going to update my knowledge to work with .NET Core 1.0 and MVC 6.
I'm asking for advice from those who write in C # and develop web applications: what else would be useful to study or should be studied concretely?

Answer 1

But I still feel like something's missing

apparently not enough flight hours of experience to feel confident in all this.
I can recommend to write some kind of project.