On the KDE side of things there is also Digikam that will process Raw files.

Personally I don't see much point in a Raw plugin for the current version of Gimp. You have to do all of your exposure/color adjustment work in the plugin to benefit from its 16/32-bit/channel processing, because the 8-bit processing in Gimp creates artifacts very quickly. So when you have done that part it is a good idea to save the results anyway before you start local editing. So you can as well switch to another application.