You could do a Bloom filter on each bucket, each of which has about 500 items. This would reduce the size of the response from about 16k to < 1k. But it would b

You could do a Bloom filter on each bucket, each of which has about 500 items. This would reduce the size of the response from about 16k to < 1k. But it would be a lot harder to use since all clients would have to use the Bloom filter code correctly.