I agree that would work for many use cases. We require tags from multiple tag groups, which is not supported by Discourse. We want to allow the new topic, without approval, but ensure the tags are correct as time permits.
I guess what I’m suggesting is a way to place arbitrary items on the review queue. Currently there are three supported types: flagged post, queued post, and user. We’re hijacking flagged post because it’s the closest to what we want, but it would be nice to place a “review tags” item on the review queue, even if we can only do so from the API.