Yeah, though I don't go so negative for it.
Every time I want to do a new version of my product, I dip my toes back into the QtCharts water and end up getting them bitten by piranhas. It is disappointing that QtCharts is so unlike the rest of Qt, which is flexible, adaptable, derivable - everything that QtCharts is not. I don't know how such a library became part of the official Qt distribution.

I have written several charting widgets of my own, the latest of which uses the Graphics / View architecture along with axes and a few other things borrowed from Qwt5. It does what it needs to do for the application (including a setRawData()-like functionality implemented in the form of an abstract "DataAccessor" class hierarchy which can pull data from arrays, vectors, item models, whatever). The DataAccessor idea lets me very quickly build a chart that draws x, y, value triples from table models simply by defining a proxy that uses only three columns. The "value" part can be mapped to a color, marker shape, marker size, and so forth.

Unfortunately, my users want something a bit more "professional" looking so they can copy images directly for publication. So I need to find something that looks nicer than what I have done and supports more chart types and options. It would also be nice if it supported 3D...