It also prompted a question about spy order; should spy orders be determined in advance? Or is it legal to think about hitting one guy, then switch target should someone else take him out first?
It is legal, clearly, since there are no written orders and no-one at the table can tell what you were thinking in advance.
I realise my original (wrong) rules implementation changes the voting strategy but would it screw things totally?
It weakens some types of Representative because of the possibility of a wasted action, where in the rules as written you can often target someone who's already revealed their own Rep secure in the knowledge that your attack will work.