Note that all screenshots are in monochrome. SunView on color monitors looks the same except for spot colors. But Open Look on color monitors switched from the crisp monochome line art here, to using shades of gray for more of a 3D bevel look.
It might bear mention that most of the OpenWindows tools seem to be done using the XView toolkit for the GUI controls, which was pixel-based, and crisp. PostScript of course could do vector drawing, but the vector-rendered Open Look controls didn't match that. When you only have a million pixels to play with, and and it also has to work on a monochrome monitor, pixel control is important for some things. So you might have the pixel-based usual GUI controls, but a subwindow in which you did vector rendering.
One noteworthy OpenWindows thing not mentioned here is that it started to support drag&drop. Tools (programs) had explicit visual drop targets, to indicate that they could receive a drag&drop.
The pinnable menus were an Open Look thing. The idea is that you'd have something like a Mac or Windows menu bar, and user could pin a pull-down/pop-up menu, and drag it to anywhere on their screen, to be like a flexible what later became called a toolbar. (We later saw things like that evolve into dockable toolbars, sometimes including in a return of MDI interfaces (one big window for an application program on the host desktop, and that program manages multiple "document" windows within it and dockable and customizable toolbars and persistent property sheets).)
It's sad that NeWS didn't become bigger. I heard a rumor in the early/mid '90s that Frame had invested in a NeWS-based implementation of FrameMaker, and got the rug pulled out from under them. But at least, as Sun was later dying, Linux and the open source around it (a different beast, but good) arose in its place.