I agree totally with that, however who will choose who replaces them?
In my opinion there needs to be a qualification competition of some sort, with my idea the country involved would choose who the wild card is, that person would then get a chance to show why he should be there next year against the competiton he will be riding against.
As a side thought the Wild Card could be the Current National Champion (or highest ranking non current GP rider), which in this country at least,would bring back some real competition and status to the British Final.