If you survey a lot of planets and explore around nearby systems when you go on expeditions, you will make so much more profit. I routinely make 500k off survey data and AI cores can be in the millions if you find a juicy warning beacon system. Narrow-mindedly chasing just bounties and probe missions is where you will run into trouble, they don't pay enough all the time justify trips to the edge of the sector. If you find them groups they can be profitable though. I'm rich enough now where i just buy the capital tanker, fill it with fuel, and explore with my full combat fleet (8 or so cruisers and a paragon or astral depending plus assorted carriers, destroyers and frigates) while still making a profit. Even with my horribly inefficient fleet, I almost always run short on supplies before fuel.