Use a local light for all the ligthning. For the first renders, it's enough I think. You'll have better shadows then. Mmh, in fact, you'll have shadows lol.
Mmh, I think that's Setekh who told this to snipes: let you pic tell a story. Don't just throw some models in front of a pretty background. First decide what you want to show. A fleet? A capship fight? Anything? Take the time to place your ships hwo you would place them in fred and then imagine how they would move in fs2(yeah, that sounds dumb, but I think it works well), Then move the camera around to have the best point of view possible.
But my main advice is related to the shadows: Try to have contrasts, contrasts make the mood of your pic, and you can only have contrasts thanks to lightning.
Ok, that's my two cents, I now let render masters like Setekh giving better advices coz my neuron is now almost dead from a very exhausting night
