the first image looks complete to me. perhaps a little more depth to it, but it would work nicely as a desktop image i think
the second image posted has neons, the light flare from these are perfectly horizontal, this is jarring considering all the other nicely organic objects in the scene.
the third and forth both have (to me) pretty ugly uncomplimentary colours and not really strong compostion - the red one is a bit more gathered though. the orange just looks like a mess.
the blue/white image is cool. that curved shape is impressive. glowing 3D sine wave generation… though the steady motion blur of the stars doesn’t really fit with the stepped movement of the sinewave. i guess its supposed to be a very very long exposure style image?
the motion blurred pointy chess piece looks like it needs a lot more work. sticking the focal point dead centre is not very interesting. perhaps show the pieces moving in all different directions, with varied blur amounts, and that angle doesn’t really do anything…