I'll be happy to add my charts to the thread as well.
I think folks should know how to read these things. For example, your chart of "Auto Air Aluminum Fine" just about gave cynical2 a heart-attack until he saw the scale it was drawn to!
The horizontal X-axis represents the colors of the spectrum the spectrophotometer measures. In my case, my spectro measures from 400nm to 700nm; mech's spectro goes from 380nm to 720 or 730nm. Ultraviolet light begins at 400nm and Infrared begins at 700nm, so mech's spectro can measure further into the Ultraviolet and Infrared spectra than mine can. Oh yeah, nm = nanometers, the frequency of the color.
The vertical Y-Axis represents the reflectivity value of each color and is where things can be misunderstood. In mech's "Auto Air Aluminum Fine" chart, the line doesn't look flat at all! It looks like it slopes steeply from the blue end of the spectrum to the red end; but if you look at the scale of the Y-Axis you will see that it only goes from 0.29 to 0.37 (from 29% to 37% reflectivity). Below is a chart of the same type of paint I made with my spectro that looks quite different, but if you look at the scale you will see the measurements are almost identical; the difference is my chart uses a Y-Axis scale of 0 to 100%. The smaller the values represented by the Y-Axis, the greater the color differences of the paint will be magnified on the chart.
