To albert:
I'm kind of flattered that you'd want to hear from me on ideas to improve the process. I saw your post pretty soon after you posted it and spent a couple hours tossing around possibilities in my head (not JUST thinking about danbooru during those two hours; I was resting as I thought about these).
Without knowing the capabilities of the moderation utilities, both in actions you can already take and ways you can modify the process:
Out of your options and based on the way the community is (as I've seen it), your current setup is the best option, but could be tweaked to make things a bit better. Here's my ideas:
-You can extend the period before something gets auto-deleted to something like 5 or 7 days, which gives more time for moderation to view the image and would make the uploader feel that it's more likely the moderation DID get to see it before it got auto-deleted.
-Unless I have it wrong, it looks like Privileged users have nothing that auto-deletes their entry after a certain number of days. If this is the case, then emphasis on checking the ones that will get auto-deleted without mods looking over them is ideal.
-Whatever your moderation utility looks like, perhaps you can create a way to break down things in the moderation queue where you can search for ones that will get auto-deleted and things that won't get auto-deleted.
-These are wrapped into the above. There are some things that might be important or more likely to be meaningful to danbooru than others; perhaps they can have categories as well. Some ideas for categories would be posts that are part of a set/series and official art.
Sometimes it's not the utilities that can be improved, but the rules, guidelines, options, etc. So, here's some for that.
-My auto-deletion appeal thread was all about how there are some images I feel would be perfectly good for danbooru but which got auto-deleted, and asking the mods to give them another look. There could be a thread in the forum devoted to it. This COULD be too grandiose and taxing for the moderators of danbooru to do on a widespread scale, I don't know the composition of the moderation team and time they can invest in it.
-Naturally, the mods have a lot of demands on their time. If a thread for people to appeal auto-deleted entries is made, there needs to be explicit and possibly strict guidelines on what people could and should appeal. I did not consider this until when I tried to appeal a huge number and was asked to go back and narrow it down to a more reasonable number.
-Perhaps there could be examples of "danbooru-quality" gray area images that would be accepted? I don't know if this one would make sense or actually work, it's an idea to help people decide if their images are good enough for danbooru. Everyone knows a stellar, spectacular image when they see it, ones they can be sure would be added to danbooru; the ones that aren't in the top 5% of art are the ones that are debatable.
That's all I can think of for now, though there may be others. I hope that's not TOO long of a post, and that it's helpful.