Darktable is fantastic for this sort of thing-- First, it's got a built in module for converting negatives that works rather well, and second, it's very easy to selectively copy/paste settings from the stack of changes you've made on one image, to another batch of images.
In fact, Darktable doesn't actually alter the original image-- it just stores the changes as metadata, and applies those changes until you export a finished image.
The interface is a bit... quirky... but not nearly as much as say, Gimp.