I'm on the fence.
I think my biggest gripe is how the U.I scales down to a 13" screen, because of the much extra space many elements now have.
The spacing on the menu bar is a joke at this size, making Bartender all the more important.
The app icons on the dock are less legible. I can't for the life of me understand why Apple didn't make them all more 3D like the new Final Cut Pro and GarageBand icons, which take advantage of the space outside of the icon frame whilst maintaining the new size.
Certain apps distribute toolbar buttons in strange ways as. Mail has less room to display the toolbar because of the way it's been re-arranged, and the Finder looks... well, less Finder-ish at the title bar.
'Reduce Transparency' now adds a black outline to windows and the dock, and makes it very difficult to see icons with any white space on them.
But there are genuine improvements to the OS. The consistency with rounded corners - particularly on menu items - is really pleasing to the eye. The Messages update was an absolute God-send. Control Centre in the menu bar is fantastic as it makes System Preferences redundant for many regular system changes. Safari is amazing.
I think the potential is there and I've no doubt that Apple Silicon Macs will be all the better for having iOS app support and the new incredible new speed, but from a productivity and graphic arts perspective, this really feels like a step back for someone who needs clear distinction between U.I elements. I actually wish I hadn't updated, and instead just waited until I purchased an Apple Silicon Mac next year.