[keyb0ardninja]

I've a similar setup as yours (https://i.imgur.com/D3McL6m.png).

You're wasting a bit of vertical space though with that empty titlebar. I turn off the titlebar for all windows in KDE Plasma and add this (https://github.com/psifidotos/applet-window-buttons) applet to the panel.

[bloopernova]

Yup, I found some css to merge the system UI buttons into the main UI bar. Thanks for pointing out that was possible!