Surely we should keep it to how it is until this season is over.
Why make the classes equal, is clear that the ones who choose FXR do that not because they want to be slow, its due to not being able to handle a FZR manly in most cases.
Leave it how it is, if you are worried about not having time to practise with patch X when it comes out, then we are all in the same boat! We all have the same time to practise, if you are still worried, then race with old W0?