I suspect we will have both artificers and psions in a 2026 core rules supplement book. Although whether the psion is a reprint depends on if it comes out before or after Dark Sun.
I suspect one artificer subclass will remain exclusive to this book though - probably Cartographer. With one...
And tens of thousands of unnamed Flaming Fist mercenaries of many different species*. Assuming your Flaming Fist character is connected to any of those is highly improbable. It's a stereotype that all Americans think all British people are related to King Charlie. Do you actually believe that...
Aren’t these all details the player normally decides? If I was a player creating a human PC with a background in the Flaming Fist I would expect to have to answer the same questions.
And if they are just some NPC guard, then you need to know different things about them. What it’s their...
DM: “In the town square you see a crowd of people gathered round watching a juggler.”
Player: “Are any of them Dragonborn?”
DM: “You see the glint of scales at the back the crowd, but you can’t tell if they are a Dragonborn or other scaly species from this range, do you want to go closer?”
Well, if they are separate settings I don’t like either of them. Indeed the reason I never played Starfinder after buying it is the inbuilt setting didn’t suit the stories I wanted to tell.