Hi.
Actually, I have the same feeling with you about Microsoft design language: it's too flat and quite boring compared to Material Design. But it also has some advantages: the three-point button allows users to expand the menu and see the description of each icon button; it works better for mouse and has better performance.
About the project, I build Modern Editor on Universal Windows Platform (https://msdn.microsoft.com/en-us/library/windows/apps/dn8946...), which is a replacement for traditional desktop platform. Therefore, the app doesn't use NW.js or Electron: much more lighter (2 MB at the moment compared to more than 30 MB of Electron) and all the APIs are called directly through WinRT (aka. more native), can work on phones + Continuum, PCs, tablets, IOT or even Xbox.
I hope this will answer your question.
