The title pretty much says it all, so I'm developing a 3d engine for Directx 11, and it's going good so far. I started using .net forms as a GUI, but then(Of curiosity), i jumped to MFC, and the app looked great, but in my perspective, MFC is badly written, and it's too complicated, meaning that some things just took forever, while it would have taken a few seconds in .net forms. But my real question is:
If i want to make an Editor for a 3d scene, where directx renders in the form( This was accomplished in .net forms), what would be the best choise of gui platform/framework?
MFC,.net forms, Qt, etc....

If you're working in a .NET based language I would definitely recommend using WinForms.
If you're working in C++ however, and if you don't want to write a managed wrapper around your renderer I'd recommend Qt. They provide a great toolset for creating and editing user interfaces, and you can seamlessly integrate their toolset with a full version of visual studio, although there's no support for VS2012 yet.

Is wxWidgets an option for me?

Yes you could also use wxWidgets for building your editor GUI, it's actually what UnrealEd uses.