I agree that the grading looks a bit flat, but if the client liked it then that's what matters. Mixing cartoony characters with realistic lighting can be an interesting new approach, can you tell a bit how you did some of the scenes? For example with the new 360 cam in V3, could you have rendered some backgrounds and used for HDR lighting and so rendered it a lot faster? I know the kitchen scene was most difficult for you, and personally I find it very bright, his shirt looks almost completely blown out. Plus all those reflective surfaces and an "interior" means you spent quite some time rendering that. Each frame was rendering the complete interior every time?
Nitpicking: There is a small sudden change in lighting with the old couple at the end, just as the split screen disappears

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