How does one reorganize one's entire Aperture library from scratch? I imported pictures into Aperture from iPhoto and since then, added a lot of new ones. I'd like to start over because the dates on the tags/folders in which the pictures are organized are not consistent.

In effect, what I'm looking for is a way to do a re-import of all pictures in my current Aperture library (not that many... just over 1,000) to have it apply its import rules/magic to have it all sorted properly.

That feels like a hack, though. Is there a proper way to do this?
By default, there is not any magic when importing photos to aperture.

Probably at that point, what it might be confusing is that Aperture has transformed your iPhoto albums to folders/projects, which are not what you exactly want.

My advise would be to create one project, move all your images there, delete all other projects/folders, and then create new projects as desired.

Furthermore, you can find a lot of articles of how you may use projects/folders to organize your photographs, like this one.