Absolutely, I think that the QGraphicsItem canvas-ish API is much simpler for what I need (a lot of custom drawing); QGraphicsScene also has some very useful functions that QtQuick is missing (getting all the items z-ordered at a given x, y position IIRC? Don't remember exactly but I wanted to try to do a port one day and missed a bunch of critical ones... That was 4 or 5 years ago though). And QQuickPaintedItem was too slow for my needs when I had tested it, much slower than QGraphicsItem for large amounts of items. With the OpenGL backend of QPainter the UI is plenty fast even on 4k screens (but even without it it's fine honestly).
What I would really like to see would be a QRhi-based QPainter implementation for things to be future proof but I understand it's a non-trivial task at all.
Also, even though QML is very nice for projects with more or less fixed UIs, for very dynamic things I find it to be more unwieldy; I reach for it for mobile and embedded without hesitation but for "traditional" authoring desktop apps I'm generally faster to develop with QWidgets/QGraphicsScene in C++.