Plasma's default is to display a panel at all times and for it to be bright. In my opinion, this is an unfortunate default and all of Plasma should switch to the hybrid approach of Breeze Dark for the panels and menus with Breeze (light) for the Application Windows.

Reasons Why Hybrid is Better:

1. Panels are always visible in Plasma by default. The dark panel is better to the eye if set to always visible.
   • If a user has a bright window theme and all windows adhere to it then not so bad. However, many applications don't adhere to that. Text Editors are a good example of being dark by default.
   • A bright panel is very jarring with dark windows. A dark panel would not be jarring regardless because it doesn't pull focus from any window theme.
2. Dark panels/menus are friendly to the eye because they are suppose to be helpful when needed but not intended to be the main focus of computing. Bright panels pull focus for seemingly no reason.
3. Hybrid approach is the most common approach and thus on-boarding of new users would be smoother.
   • Windows, GNOME, Cinnamon, MATE, Unity (I know but still relevant in this discussion), and many more use a hybrid approach for defaults.

My Counter-points to Hybrid Counter-points:

1. "macOS uses a light panel design"
   • macOS has theming guidelines that most applications adhere to, not much an issue for them.
   • Apple hardware has a bright aesthetic. A bright panel next to hardware that is also bright isn't as jarring because the contrast is minimal.
     • 90%+ of PC hardware has a dark, even black, aesthetic so the bright panel of Plasma can be very jarring.
     • Dark panel is not even jarring on bright aesthetic hardware so there isn't a negative with hardware that isn't a part of the 90%+.
2. "This is not how KDE/Plasma does it officially".
   • If everyone just stuck with defaults for everything then innovation wouldn't exist.

I can provide screenshots if desired but you probably know what both current Breeze themes look like and I am simply suggestion making a Hybrid theme combining the 2 where it makes the most sense.