Science & Industry

A fast and easy way for you would be to go into t2 component production: all those intermediate goods that are needed for t2 production, like thermonuclear trigger units, pulse graviton generators etc. .
There is a manageable amount of those blueprints (not sure, but I think no more than 20), each blueprint costs about 5 M if I remember correctly and can be very quickly researched with an optimal ME mostly at about 5 (although you will need some skills for the research, like Metallurgy 5 for example). With a good assortment of these blueprints you can settle near a trade hub, buy moon goo, build those t2 components 24/7 and sell them at the same hub. This will give you a steady and reliable flow of income.