1. The Rhapsody developer previews, which are NeXTstep with a menu bar at the top and desktop icons, and a Platinum skin.
2. Mac OS X Server 1.x which has cascading finder windows, an icon view by default, and some other things much like that.
3. Mac OS X 10.0, which I used, or tried to use, as a daily driver, with a broadly Mac-like experience with an Apple menu, but with app names next to it containing global "about" and "quit" options, and so on.
It never did acquire any of the nice stuff that came in with System 7 (e.g. drag-and-drop customisable Apple menu stored in folders in the System Folder) or MacOS 8 (e.g. folder drawers that shrink to tabs).
Yeah, a lot of those “blue” features never were adopted or came back. The whole spatial Finder concept was lost.