No fractional-reserve banking does not imply this - there could be lenders (whether goblins or wizards) with a large supply of their own gold which they use to make loans. Or landowners could sell property with a "rent to own" payment plan. Fractional-reserve banking is only necessary if you want to lend someone else's gold.

Do you mean what Eliezer calls the Machiavellian intelligence hypothesis? (That is, human intelligence evolved via runaway sexual selection--people who were politically competent were more reproductively successful, and as people got better and better at the game of politics, so too did the game get harder and harder, hence the feedback loop.)

Perhaps a species could evolve intelligence without such a mechanism, if something about their environment is just dramatically more complex in a peculiar way compared with ours, so that intelligence was worthwhile just for non-social purposes. The species' ancestors may have been large predators on top of the food chain, where members are typically solitary and territorial and hunt over a large region of land, with its ecosystem strangely different from ours in some way that I'm not specifying (but you'd need a pretty clever idea about it to make this whole thing work).

These aliens wouldn't be inherently social the way humans are, but they wouldn't be antisocial either--they would have noticed that cooperation allows them to solve even more difficult problems and get even more from their environment. (Still in a pre-technological stage. Remember, something about this environment is such that it provides a nearly smooth, practically unbounded (in difficulty) array of puzzles/problems to solve with increasing rewards.) Eventually, they may build a civilization just to more efficiently organize to obtain these benefits, which will also allow them to advance technologically. (I'm probably drawing too sharp of a distinction between technological advancement and interaction with their strangely complex environment.)

They might lack the following trait that is very central to human nature: affection through familiarity. When we spend a lot of time with a person/thing/activity/idea, we grow fond of it. They might not have this, or they might not have it in such generality (e.g. they might still have it for, say, mates, if they reproduce sexually). They might also be a lot less biased than we are by social considerations, for the obvious reason, but perhaps they have less raw cognitive horsepower (their environment being no substitute for the human pastimes of politics and sex).

Recklessly speculative, obviously, but I gather that's all we can hope to offer to Solvent.

Species that specialize their intelligence like insects becoming workers/warriors/queens/drones etc. but for intelligence.

Humans do this (and increasingly so). e.g. we have physicists, mathematicians, economists, psychologists etc.