My suggestion is to avoid random patterns for the most part, which it looks like you've done. Regular patterns with slight tonal variation from one panel to the next seem to work best. I actually prefer delineating the panels with those tonal variations rather than actually outlining the panels, just looks less like '90s TV sci-fi CG.
Try to avoid panel lines that intersect windows, vents and other apertures. They wouldn't build a real ship that way and the eye instinctively registers it as unrealistic.
Don't forget hatches and access panels, though they should be minimally and logically placed. If your UV mapping allows it, you might also include some markings, decals, signage, etc. I did some warning indicators for the maneuvering thrusters in one of the concept sketches that I could send you. I also had red markings surrounding the lander module bays that you might consider reapplying.
Oh, did I send you the name and registry number graphics earlier?