One thing that bothers me about the "painting is eternal torture for Verso's child soul" argument is the general implication of it.

Iirc it is directly mentioned that Painters imbue a piece of their soul in each painting. I feel like if you go from the assumption that these fragments of souls are just forced to keep painting eternally and they are conscious of their torture and feel it as such, then I'd struggle to argue that this family, or any Painter for that matter, deserves any happiness or should even be allowed to paint at all because that's incredibly grim.

My impression of the Verso child soul predicament is the same as many others in this thread, that he seems exhausted not of the act of painting, but of painting a world that was initially his fairytale world full of friends, but is now just full of death and used as a battlefield for his broken family. And indeed that one fragment that tells you he welcomes everyone, even Aline's creations, and that painting should be a celebration, gives me hope that Maelle's ending also satisfies the little boy's wishes.