Well, it's a shame that there aren't more people offering help to the budding space artists out there. I caught the last image you posted. This one is improved comapred to the last, definitely. I'm going to focus more on the negative points - don't take it in a bad way as there are a lot of positive points too. The clouds are lacking in definition. They come across as a slushy haze. Adding definition to clouds is no easy task. Maybe hand painting in contrast will work (every cloud has a silver lining). By doing this, it should also make your lightning stand out a little more easily. The other thing is that your lens flare seems to be lacking in contrast, and once again comes out as a kind of grey haze. Either try adjusting the curves on it, or setting its blend mode to linear dodge rather than screen. If you've already done this, I'd go down the curves approach, or even make it smaller and then increase the brightness. The planet is lit from slightly the wrong angle assuming most of the light is coming from your flare. A simple rotational transform can fix that easily. Oh, and the glow around the planet stops rather abruptly. I personally believe that the writing detracts from the image somewhat, but that's just personal preference. The blue one is nice. Have you tried desaturating it slightly to get that washed out 60's scifi look? The N1 already has that great feel to it, so it could work wonders - just an idea. Anyway, as I said, this overall is a good composition, and there's a lot of positive points to be said about it.

I think it's a nice render, except for the writing. That ruins it. You might try some falloff on your atmosphere to have it slowly fade out.