This is probably anecdotal but...

The best quality affordable Chinese frames I've tested (stiffness, fit and finish, tolerances) have come frame companies/factories who do NOT offer up custom paint jobs and decals. Basically the OEM factories.

However, brands/agents who offer up all these crazy paint options and put a priority on aesthetics are probably hiding something in the QC department. Just spend 5 minutes the IG accounts from TanTan, Hygge, and even Elves.

I would rather a factory tell me they don't offer paint jobs because their focus is on the production and QC of their frames and components themselves.