This is very cool Jayesh!One thing I always found useful in drawing/CAD tools was a bunch of orthographic views off to the side of the UI - for one thing, they help align things, maybe with a grid.
How about an export feature, to download models, as .DAE or .OBJ and .MTL?
Pretty cool! You can try something like SketchUp, where you can sketch
a profile and drag extrude it, though I think SketchUp has a patent on
that (but should be easy to circumvent - just don't use the mouse to
drag the profile, instead use a dialog to specify the extrude length).
Also a toggle between a 2d sketch view (to draw the profile) and the
3d view, will be helpful.