In Visual Studio 2017, you can select Tools > Options > Environment > Startup > At startup: Show empty environment. This prevents the Start Page from displaying when you launch Visual Studio, and in previous versions it prevented the Start Page from appearing when closing a solution.
In Visual Studio 2017, though, it seems the designers chose to show the Start Page after closing a solution, even if the option was for an empty environment on startup.
Are there any creative ways to get around this until the Visual Studio team decides to provide a reasonable option?