Bad blending, stretched and elongated images, more than one focal point/render, very large, no border, bad looking font, bad renders, and some clashing colors here and there.
I'd give all of them somwhere around 2-3/10, but for a beginner you're pretty dencent. The problem is that you're using the wrong techniques to create your effects. Start by reading some basic tutorials that go in to blending, lighting, and flow. Then advance in to brushes and C4D implementation, as well as how to use smudging.
It'll take time, but if you keep working you'll see massive results in just a few weeks.

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