Way way lower.

Well, in fact, no. I would tie the ability to buy ships to ranks. All of them. And adjusted the missions in a way that allows you to earn approximately one rebuy cost of your maximal allowed ship tonnage in an hour.
Example - rank 3 (Novice, Peddler, Scout) would allow you to fly ships up to 100 tonnes and your hourly earnings would be about 200kCr, while rank 6 (Master, Broker, Pathfinder) would allow you to fly ships up to 400 tonnes and upped the earnings to 4MCr/h. Elite would allow you to buy any ship you want and your mission rewards would be about 20-30MCr/h. Etc. Something like this.
How about that?