Composite materials

In this game, I know that you can change the way the part looks (example: insulation or riveting) however, I would like to see the addition of other materials such as carbon fiber, or for the game to specifically tell you the material you are using. Along with this material change would be a change in the crafts properties such as heat shielding or re entry heat damage temperature. For instance aluminum would melt before stainless steel etc. Material change would also affect cost and weight, carbon fiber, light and expensive, stainless steel, heavy heat resistant and inexpensive.
Of course, many people like to break the laws of physics in simple rockets using the tinker panel. This will certainly let you forget about the material you're using and just make it simple.

This is just an idea, hope you like it!