Great read.
As for those who want a good finished model, look at the 2005 Star Wars Miniatures AT-AT.
At about 13" high, it has no articulation, but great size and paint, and you can probably find one for under $100.
Here are a few pics found on the web, to show scale. For more pics, a simple search for 'Star Wars Miniatures at-at' will get you plenty.
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