So after a lively discussion this morning with the rest of the group, I've somewhat revised my plans for rearranging the DLLs. Instead of adding one new DLL to the project, I'm adding three, because I've been assured that no one minds having lots of little DLLs. I recall hearing the opposite not too long ago, but I guess we've always been at war with EastAsia. :)
On the other hand, the net amount of work that I'll have to do is a lot less this way, so that's a plus!