A choice made by whom? For who? Not you. That's why you have to resort to some bizarre layout, with some magic 67% size concerning both WM and individual windows' panels.
A code editor does not need a terminal, because everyone already has a terminal that is not restricted into one IDE window. Do you run tmux inside your IDE's terminal? Do you never use any other terminal? You shift the goalpost to video editing, what is the specific double-67% requirement now?