It seems completed cities (as well as in progress cities with equal percentages) get sorted alphabetically… but reversed. It probably makes more sense to flip that around (Alternatively, by number of streets it took to complete that city, or preferring “real” ones over nested ones)
Or better yet, a “sort by” with all of these options!
The next release will fix that sorting.
Some future release after that will include a whole host of sorting options throughout the site.