Thanks for the input and kind words.
Indeed right now the gui and display is not super responsive and is intended to a 1080p resolution (which is kinda dated).
For rts I think it is important to keep a fixed game screen resolution so that having a bigger monitor does not result in unfair advantage by making more information visible on one screen.
But zooming in should still be an option.
Right now you see four time more area on your 4k screen compared to mine which indeed result in everything being very hard to tell appart.
There will probably be a complete rework of the UI at some point since I am still getting into Godot I am making rooky design mistakes.