Yes, I agree that it's the fine distinctions at the upper end that are hard to make. But if we're going to eliminate 50% of the proposals, is that really going to reduce the amount of time people spend on them? It might reduce
reviewer time (which would certainly be welcome!), but I'm not so sure it reduces the submitter's time.
It comes down to whether the large amount of time spent is from people polishing and re-submitting stuff that's good but not "great", or whether it comes from the initial stages of getting something to that good quality to start. In my experience, it's the latter. And if that's typical, then I don't see how the lottery helps.