Plasma, Plasma, Plasma Chameleon, you come and go. And here's a detailed article showing how to transform the Plasma desktop to look and behave like Windows 10, including new, custom global and desktop themes, window decorations, fonts, colors, wallpapers, logo, tiled menu, search, some other tips and tricks, and more. Take a look. https://www.dedoimedo.com/computers/plasma-look-like-win10.html Cheers, Mrk
At the end of the posting, you write, "If you fancy other guides, please do tell, and I'll see what I can put together." Yes, please! I would love to see a guide with instructions on making Plasma (in Kubuntu) look like Windows 7, or (better) Vista, or (best of all) Longhorn. I've lost track of the amount of time I have spent looking for themes and UI elements to piece all of this together, and it still doesn't look right. And you are correct: searching for this stuff is a slow, hit-and-miss proposition. Many Vista/7 lookalike themes found via Discover, or in the KDE store, just don't work (won't install) any more, while others come with their own variations ("inspired by Windows 7", blah blah blah) that of course aren't quite the real thing. Here's a vote for more such guides!
For an alternative to Breeze10 for Plasma window decorations, I think ClassikStyles is a good option. It has prebuilt packages for various distros, and is actively maintained as of writing. It's what I'm using for my Debian+KDE setup. ClassikStyles link: https://github.com/paulmcauley/classikstyles My settings for ClassikStyles: https://imgur.com/a/JgfNBs0