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This is somewhat related to a question here on meta about whether the number of questions in the "Most Delete Votes" list in the 10k moderator tools should be increased. I looked for that question every way I could think of, to add this as an answer (if it wasn't closed), but couldn't find it.
It just struck me that when I'm looking for questions to vote to delete, it does me no good to see questions I've already voted to delete, or questions that have been migrated or locked. The list would often be long enough if such questions were omitted.