You lack of color scheme in the two first. They are very chaotic, but not in the good meaning of it, these pictures are quite a mess.
The third one has the best color and kinda reminds me of a map, but its too simple.
All of them lack of anything that would call my atention, these pictures dont really say/represent anything, not even good looking abstract. The only thing I like about the second one is that it looks like DNA. But nothing else.
You need alot of practice imo.