I agree that the details here are inconsistent and too low contrast. I have to zoom in considerably to see that there are any details on the cart body itself: it looks flat and solid at first glance. The anti-aliasing on the wheel also looks blurry.
It looks like a nice start but there are some major problems
The shading is jarringly inconsistent. Wheel and umbrella are flat shaded, yet sauce bottle and snags show some shading. What shading there is is far too low contrast.
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It looks like a nice start but there are some major problems