Personal simple statusbar script. https://gitlab.com/-/snippets/3715695
Works best with Humanoid colors.
A question with no right answer, because it is a matter of taste and habits.
Both are very much sophisticated desktop environments which very useful defaults. Neither Gnome nor Plasma are too complicated for beginners and can be customized easily. If you want to you can go very deep into the customization too.
You seem to be aware of many things.
Just for communication you are using more unfree tools then free and more then in the other categories.