Michael,

While I certainly agree with you regarding the ancillary functions of lighting, camera, mapping and material handling, there might be a way to ignore all of that.
You could possible just create an ambient occlusion lit scene and render it with the camera and light positioning of the current viewport. Some examples:



<https://d1a9v60rjx2a4v.cloudfront.net/2013/10/02/23_14_29_6_screen1_1.jpg>



You could offer the option of overlaying with wireframe:



This would have the advantage of people able to 'visualize' their design, which is really important when "sketching" in 3D. Many times I've noticed a fillet is too small, or a detail too large ONLY after I've exported and rendered the MoI3D model.

Just a thought...