The web app allows rapid 3D design iteration and support for CAD formats.
It’s long been a pain point when developing a Unity game: having to use MonoDevelop as the IDE. Originally I never thought it was that bad, but after using Unity VS with Visual Studio on my Desktop ...
There's a better set of tools than using Windows Presentation Foundation (WPF) straight out of the box: WPF plus Prism (formerly "Composite Application Guidance for WPF and Silverlight") and Unity.