I think it's time to add ship parts. I offer the following for discussion:
For armor plating, I colorized the current lead_armor_plating.png grey image to get the other images, because it is a really appropriate image for armor plating - well done!

crystal_armor_plating.png
In this image, I pulled the pink color from the mining crystal color. I thought long and hard about somehow integrating crystals into the picture, and discovered it was best to just colorize it.

rock_armor_plating.png
In this image, when I think of rocks, I typically think of brown and grey, and since grey is in use, I chose brown. I pondered about somehow integrating rocks into the picture, and discovered it was best to just colorize it.

neutronium_armor_plating.png

zortrium_armor_plating.png
Of these last two, I just chose hues that were separate and apart from the other colors. There is still room to add other hues, if other armor plating is added to the game.
Now for some originals, using the basic tiny hull, since it is most familiar to the players:

absorption_field.png
In this one, the description says that it makes the ship black, so hence it is black. I felt hard edges are best.

dimensional_cloak.png
I enjoyed doing this one. The way the dimensional cloak cloaks a planet is what I borrowed from to cloak the ship.

phasing_cloak.png
In this one, I took the ship an made the opacity to %36, as if it is fading out. I added red waves per the description, so they would stand out. I believe they are balanced.
Imagine all of these on grey backgrounds like in the game. I had added them to the game I was playing, and they worked well / looked good.
Well, now you have it. What do you think?