I'm going to start with the obvious point which you need to fix. Don't stretch out the render like you are. Hold shift while dragging from the corner and it will retain it's size ratio instead of making it distorted like you do.
As for the actual pieces, it only seems like some fractals in the background with a render slapped on it, the second one made a little darker and the third one with a red/blue/yellow gradient map on them. I'd go with the first one being the best, but don't just make random things and throw them together. Try to get a sense of flow going and make everything go together, if you know what I mean.
