Take baseline image and make colourful / vibrant image for A5

I have a basic image demonstrating my concept for a spaceport. This is now being used on an A5 flyer and therefore I want to make it more vibrant (e.g. adding colour) to attract attention. However, it is important that the baseline remains the same e.g. airport, runway towards sea, propellant storage containers, hangar, mobile radar, airship, spaceplane, business centre, etc. Note that the text in the business centre can have altered font to make legible or removed if not practical for A5.