I've been using Visual Studio for a long time. Very good it is too. However, it is heavyweight; it does far more than I need. What I really want when I'm working is a fast snappy editor, with intellisense and debugging. What I've basically described is VS Code. It rocks and has long become my go-to editor for TypeScript.
TypeScript first gained support for tsconfig.json back with the 1.5 release. However, to my lasting regret and surprise Visual Studio will not be gaining meaningful support for it until TypeScript 1.8 ships. However, if you want it now, it's already available to use in beta.
Do you like to separate out your unit tests from the project you are testing? I imagine so. My own practice when creating a new project in Visual Studio is to create a separate unit test project alongside whose responsibility is to house unit tests for that new project.
OK the title of this post is a little verbose. I've just wasted a morning of my life trying to discover what happened to my ability to debug JavaScript in Visual Studio 2012. If you don't want to experience the same pain then read on...