If you do want to include shades of orange or red within your gray color scheme, there are ways to do so, but it's important to get the tone and saturation levels right. 'Orange with some brown in ...
You can specify colors that do not have a predefined SAS color name by using the RGB, HLS, HSV, CMYK, or gray-scale color-naming schemes. Predefined SAS Colors That Can Be Used in SAS/GRAPH Software ...