You can spread them a bit, at least enough to avoid weapon overlaps.
Otherwise a single small (or even medium) could do the trick as you said. Also i noticed that the small ship is darker than the other, it's a bit strange. Either you brighten one or darken the other but try to keep the same tones if possible. To stay on the colors, currently your two ships have a very Tri-tachyon feel. Maybe that's what you want but if not, perhaps trying some other color scheme?
Edit: Here's something that might give you ideas.
Ryxsen, i think no one really said the your dazzle camo is bad, it's just that pure grey is a bit... Dull. You can either recolor it with a bright yellow but you can also keep the original dark grey but with a veeeery slight touch of color to make it more vibrant.
Just a slight hint of dark red on the right one. By the way my only other gripe is that there's no difference between the engine parts and the armors plates, they're basically the same color and tone. At first i would say to darken or lighten the engines but with your sprites already dark i'm not sure... Maybe it won't be apparent in game with the engines "flames" though.
Edit 2: And while i'm at it, i'll post the last ship that DR asked me to sprite. Because why not.