The first one is good. It has nice colors and the simplicity makes it pleasing to the eye.
The second one is not as good as the first. I don't think the image blends with the background as it should. Perhaps, you can try by changing the colors.
The third one is also good. The image is nice and the fact that you included an animated text gives it a nice touch. However, I don't like the colors on the right side (you can see the pixels).
The fourth one is too simple.
Anyhow, this are only my personal opinion, hence they are not absolute answers for everyone.
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