The Inactive/Activate feature of Version 10 is extremely nice. However, I would prefer to have the StandardForm style with the regular Black font, just as with TraditionalForm. This does not impinge on the functionality because the Tooltip on an Inactive expression gives all the relevant information. If you want a standard Black font you can include the following Style definition in your stylesheet.
Cell[StyleData["Inactive"], FontColor->GrayLevel[0]]