I spread my Obsidian window over two monitors, which allows a huge number of panes and can do what you seem to be suggesting you want.
I would, however, support a floating/pop-out window for editing. Many editors, word processors and writing programs have them because it makes writing easier without losing fast access to the other functions. Also for reducing distraction.
In my case, it would enable having multiple documents open and visible and popping them out when I want to write in one.