so we have talked about all of the factions, except for the MG.
what we know: the mercantile guild came about after a plague struck the lands to the south, decimating the population and driving the pilots across the land to desperately find a cure for their country-men and -women. In their travels to find a cure they developed a large network of contacts, when the cure was found, they used these contacts to create a huge trade empire. they have outposts all over the world, and trade routes connecting presumably most if not every city.
they control territory to the south in an area called "the vastness" and their capital city is Vyshtorg. Their bird is the swan, their colors are gold and white. the Mobula is based on a Mercantile guild design, having a lot of storage space for transporting goods, good visibility for spotting ambushes, and LOTS of guns for fending them off. the railings are sophisticated but not ostentatious, as the wealth brought by the trade empire has not caused them to forget that their forefathers created the trade empire to rescue their people from plague, a plague which claimed the lives of too many of their citizens.
nowadays their trade empire spans across the world, but because of the ubiquitous dangerous from raiders of various kinds, they have a vast naval fleet to perform escort duties and protect their interests. they have been in some kind of conflict with the Yeshans for a while, although i think i remember someone from muse saying that the conflict had died down some or even completely these days, likely due to either territorial disputes along their mutual border in the south-west of the map or the arashi's continued attacks on MG convoys of goods through the arashi desert and the wastes (the arashi desert it stands to reason is conrolled by the arashi, and we know the desert nomads, who I'm presuming are the arashi, captured Nalm because of lusse's travels entry on battle on the dunes, so it stands to reason they control the desert between nalm and the arashi desert itself as well, if only because no one else could live there even if the wanted to, which they don't. I would love to hear from muse if this is incorrect)
SO: this is some of what we know, and some of what I have guessed. we are going to pass out of the canon into my feelings on the MG. some of it is shards of canon sourrounded by my own embellishment, so some things might make you think 'no duh, we already know that from the faction feature article." Yes you might very well have done, read on, there's more.
i imagine that the mercantile guild traders are like the elite of any large trade city. they are dressed impeccably (although because of the history of the MG, not ostentatiously.) we know they can speak many languages and can make a passable job in local customs of various kinds, especially in areas with which they trade often. the merchant companies themselves, although from a tradition of selfless service to the national benefit, have followed the arc of history away from altruism towards self interest. while some social conventions that are nods to the more idealistic age are maintained, the merchants and their companies serve money: that which allows them to survive as a merchant, and to thrive as such. they are 'ruthless operators,' as we heard from the prologue video, who survive most likely because they value so highly their own survival (and by that I, of course, mean the stacks of gold seen in the same.) the mercantile guild acts with all the compassion of a epidemic, when they need to, ironically. the design of the mobula suggests something about their psychology: they are not at all squeamish about using violence. you would expect a ship designed to defend trade caravans or trade goods to be able to defend itself against attack in some kind of reactive way: guns on the sides and back, where danger might be lurking from a hiding foe. what we see is a ship that is designed with excellent sight lines, and is intended to sight, turn to face and engage fully, overwhelmingly any threat to the interests of the guild.
That is how i imagine them, chime in, how do you see them?