- The Hotbox menu, notice the cardinal (North, South) menus, which are large hit areas
https://www.youtube.com/watch?v=F_MJrYzwNyA
- The Node editor. It does the work of many older interfaces.
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Not complex, but clever and useful:
Corel Draw (at least in the older versions)
- Having pages (instead of artboards), you can easily duplicate a page, and PageUp/PageDown see the evolution of the design. Likewise, for comparing the last changes.
- Ctrl + click a color in the palette, tints a bit the object color. Nice for making colors play well together.
- Double-click a curve and adds a node (without having to select another tool)
https://i.kym-cdn.com/photos/images/original/000/529/129/f62...
Mac and Windows have been trying to become what AOL was quite a long time ago.
Complex UI's won't seem well-designed.
But, I would say that UI features like the MS Word ribbon interface and Slack's side menu system are great examples of well-designed complex UI's