Ive thought about how players can identify ships in a vast dark space and i was browsing some forums and saw this idea
engines will release trails of smoke(could be some chemical cloud) in space or non-atmo planet/moons
this would make cargo trucking more safer as you can see if there are trails of smoke/chemical-gas around the area
ps. if you want you can even make it cosmetic as in players buy different colors for their trails of smoke and their could be a stealth part which you can make/buy to add to your engine so it releases no trails