All existing (public) classes (internal or mcc) rely on getting AsMinMax() for layout.

Most apps rely on/use the existing layouter.

Custom layouts do exist but they are restrained to special cases and often only use classes defined in the same app (Ambient panels are such a case).

So someone would need to write a new layout routine that is versatile for most use cases, doesn't break old code AND is significant better than what we have.
To make full use of it one would also have to atleast touch all existing classes, at which point you could just put some "Amiga paint" on QT.......

As for CGX (refresh) not being needed, it is just as MUI an outdated design showing it's age.
If we are throwing out the old stuff, why not create a CGX_V6 that can stretch a screen over multiple monitors, maybe even connected to different cards?

Same "oh that would be nice" can be said bout almost every other part of the OS........

[ Edited by Kronos 22.09.2019 - 15:27 ]