You know… something like a French curve could be really useful too. If you could hold the french curve in one hand and snap the drawing tool to the closest point on the curve when you begin to draw. Actually. If you could have a small set of simple drafting guides in your non drawing hand would be really cool too. I myself undock the main menu from my non drawing hand pretty much all the time. If you free that hand up, using it for guides would probably be really great.