With Wintermute you can use the regular 2D walk area, the shadow the character casts is actually a 2D image which moves about with the character, the light ource I would of thought could be done the same way Visionaire does it altready.
For me the trick will be using a file format that can be used from free or low end commercial software, WM was great if you owned Max or Maya.
There's some nice tools for baking shadows, the new Blender is pretty awsome and doesn't need much Blender know how to use the bake tools.
There's a nice 3D called DAGE which uses baked textures rather than relying on dynamic shadows
As long as the character looks part of the scene I'm all for the most simple form possible,
