I'm not sure what the categories of talents would be, so I'll take that liberty and I'll assume they are elemental: Fire, Water, Earth, Wind. I also assume a lot, but I'm pretty sure this fits into all your constraints. (I would suggest giving more info on your world though, it has started to feel like I am writing your story)
Fire in my mind is a fully destructive talent.
Water is a fully restorative.
Earth has to do with the creation of stable objects and the halting of moving things.
Wind is focused on the destruction of stable objects and the production on moving things.
So someone with the power of fire would be used for soldiers yes, but also would be likely responsible for being the literal engine room of society. A resource of intense heat could be contained and used to spin massive turbines creating a wealth of electricity, or even just improve the production of mills or steam powered vessels. I see the fire talents being a sub-class almost, used exclusively for labor tasks and fighting the wars of the nations.
Water talented folks would be the world leaders, because their restorative power put them at the top of society; the offspring of medicine-man type leaders. Everyone would flock to the restorative members of society, so that they would have the highest chances of living and they would be held in high esteem. The water talents would be the best medical staff in the world, but would also be experts in things like climate control creating rooms like freezers and potentially creating objects that can cool a room passively by infusing it with their power. Water talents would be able to walk on water and read the oceans and sky, so travel by sea would also focus around the water folk.
Earth Talents would be responsible for being the cities great architects, and also be the crafts men of the society. Earth power is not only pulling large amounts of stone from the earth and bending metal or sand, but also the working of those things pulled from the ground. They would be blacksmiths, leather workers, jewelers, brewers, wagon-makers etc.
Wind talents would travel, because of their ability to glide on the wind. To some it may seem like they can teleport short distances, but in reality they can create small vacuums in the air that their body can fill quicker then the human eye. They are also often found at sea, because they have some control over the winds and can read the sky as well as a water talent. They also would be the more delicate craftsmen, who would build intense mechanical devices like steam powered mills, windmills, and blimps (if that exists).
Commons would be able to preform any job, just worse then any other specific Talent. Their power comes from the combination of the elements, so for example instead of just using fire to power a turbine, they could use wind and fire to generate higher heats then fire alone. They could use earth and water to create irrigation systems for farming.Any job a machine does today, they could do to some capacity. That's why they are valuable, they are the most dynamic tool in a country.