Off-topic about tangible/comparable progression:No, it's people like you who are missing the whole playing the game thing. Many people play games to actually be good at them, in a measurable way, which games are made for in the first place.
I thought three of the objectives of ED was to become ranked Elite in Combat, Exploration & Trading. As is working with other CMDRs to help minor factions improve & expand. Being a feared pirate/killer with an enormous bounty on your head.
Having lots of credits is indeed a goal too, it shows you can earn lots of credits. Having more credits makes other goals easier to obtain, but is not a prerequisite