I have done a lot of sci-fi scenes in blender now, however, I have never had many peoples strong opinions on them. I normally go for a dirty lens/lens flare sort of look as I find it is good at hiding bad points in a scene and generally makes things look good in my opinion. From the image I have put here of something I have made recently, what can you say about this scene? I can upload some more images soon if asked.
This is my first post on this forum, I’m just trying to make a start 
Thanks!
You’re obviously off to a great start here. the idea of the scene is good (great star backdrop!), you’ve got some good ship designs going there, keep it up!
I’m gonna be honest with you, though, post-processing and glares are not meant to cover up bad points in a scene as much as they are there to supplement the scene. Its been my experience that if I have some bad points in my scene, the only way to fix them is to improve the scene itself, not try to cover it up with a lot of glares. Doing that usually just makes it more obvious that you are trying to cover something up in the scene, and can lead to some serious visual confusion.
A great idea would be to look up images from sci-fi movies, or even real-life photos of how glares and flares show up in real life. This can show you where it is appropriate to put in these glares, and where it is an unecessary use of space. If the bad points lie in the modeling, then focus on that until you get to the point where the problem is fixed. By that time, you’ll have taken what’s already a great start and make it phenomenal.
Again, a very good start!
Thanks for your feedback, I got the idea to use lens flares and lens dirt from looking at Mass effect and the new Star Trek space scenes. I know what you mean by the fact I shouldn’t cover up things with glare effect, i’ll try take note of that in the future. 
