I think the show is
clear, but not very
explicit. They don't beat people over the head with this stuff because it's boring to most people.
So, a few thoughts. I think one primer for Star Trek economics is S1E25. Offenhouse, just out of cryonic sleep, really wants to get things rolling and demands to talk to the captain. To demonstrate his seriousness he points out to Riker that the compound interest on his accounts is probably enough to buy the Enterprise. If his accounts are legally intact, they would certainly represent an astronomical amount of wealth worthy of respect, but Riker treats this as the goofiest thing anyone has said to him all week and blatantly blows him off.
Later on, the captain completely fails to take his demands to talk to his lawyer about his property seriously. Later still, "material needs no longer exist." It's a little unclear whether it's even possible in the present for someone on Earth to be a tycoon the way Offenhouse used to be, but I'm pretty sure none exist on TNG. (am I forgetting anybody?)
There are certainly tycoons and accumulators of wealth away from Earth in the greater Star Trek universe, but they tend to be portrayed as buffoonish (Ferengi) or blatantly evil (Kivas Fajo) and they serve as a contrast to the Federation's way of doing things.
> Economic roles are not given to people according to a social engineering plan.
I think we should probably infer that social standing and power follow from participation in the Federation, since it seems to usually work that way. When Picard comes back to Earth in S4E2, there's a fairly prominent civilian job (run by the government) lined up for him. Successful scientists, successful anything, always seem to have Federation ties. (the only counterexample I could think of offhand was the evil scientist who built Data)
There's a question of POV here - maybe there's some whole other, much more capitalistic, economy in the Federation that just isn't shown on screen. I don't think so.
> What we really get hints at is that most things that we consider scarce in the 20th/21st century are not scarce in the 24th century. This seems to be achieved through technology that easily gives access to much greater quantities of usable energy than we currently have access to
One of the things that Iain Banks describes really well in the Culture novels is how, in a post-scarcity economy, controlling the replicators (or whatever) means having power. With regard to Star Trek, I just can't think of any examples offhand of serious resource allocation happening on Earth or within the Federation based on a capitalist process of price discovery. It seems like the entrepreneurs have to get out to the frontier.