I don't know of a way outside of modifying the roles to accomplish what you want. If you'd rather not make all those copies and have to reassign them, you can always just modify the existing roles. That's probably how I would proceed were I in your situation.
You can make a backup of the role by downloading it first to your pc. In PFCG type in the role name, then go to the Role menu -> Download. Save it to your PC. To restore the role back just take the upload option.
