Okay, let's concentrate back on the Social Pillar of the game and not the Ressource Attrition Combat Strategic game play

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I think what this discussion needs are more concrete examples of actual play.
So let's take my game from last sunday.
There was a social challenge:
RETIRED PIRATE TRYING TO TRICK PARTY WIZARD
The session Prior the Party plundered the ruins of the thieves guild (which they had blown up some sessions before) and came across a ledger of secrets about the inhabitants of the city they are currently in, which the Thieves Guild Boss collected.
Secrets like one of the guards has a gambling problem, the gnome shop owner who is right now improving the Ship of the Party has a drug problem etc.pp.
One of the secrets was, that one of the fish sellers on the market was a former pirate.
And the Party was actually looking into finding out where a certain pirate base could be in the asteroid field (it is a spelljammer campaign).
So the party wizard went to the fish seller (while the other characters were preparing for the next quest) to speak to him and maybe see if he knows where this certain pirate base could be (called Skullhaven).
So the player character and the "Pirate" just talked a bit, the wizard let it know subtily that he knows that he was a pirate. The pirate of course denies such things, but let it slip, that he maybe know what asteroid they are talking about - doesn't the wizard maybe want to but some night scavver meat? Just 5 Gold. After overpaying for the fish, he tells the wizard he knows about the asteroid, even visited once, as an honest trader of course, but wouldn't advice anybody to go there. The place is cursed. But if the PCs has a map, he could show where it is ... the PC doesn't have a map? He could organise one for a small fee of 50 Gold. The PC should come back in the evening.
That all took place in like 2 to 3 minutes. Me writing this down took probably longer than the actual play time between Wizard and Pirate.
There were also no Rolls involved so far.
So the Party thinks, that maybe they can buy a Map of the asteroid field someplace else, so they decide to go to a shop later, want to buy a map, but the last map was just sold, for 1 Gold, to the pirate ...
So a little pissed about the pirate, they decide to visit a tavern run by a retired adventurer the party saved at the beginning of the campaign and behold, that one has a Map, too and gives them to the party for free, because, you know, life debt and friendship.
But in the evening they still decide to visit the pirate - because they still want to find the location of the pirate base - so they still feint interest in buying the map, but want to see it first, so the pirate shows them the map, they can see, that the map they have is similiar to the pirates map, remember the location of the base and leave the pirate without buying the new map.
Like, all played out at the table.
The whole thing was fun, the Wizard nearly being tricked to overpay for the map, but at the end the party tricking the pirate ...
And all of that with only maybe one or two insight checks to see if somebody shows signs of deception.
I don't see how this could have been improved by adding more mechanics to it.