Hello Toxic, welcome to the heaven and or hell that is world building, I should know I spent the past year doing little else as far as writing is concerned.
First off I'd like to say I quite enjoy the concept for a setting.
So allow me to start shooting off some questions like a machine gun.
First question, probably the most important. Are you building a world, or a universe?
Is this Earth, or some other world? (Insert fantasy world name A, B, or C. For instance my world is called Mithra)
What time period is this? Are we looking at assault rifles and computers, muskets and ships of the line, swords and castles, etc.
Of the characters you have, do you have any potential MC's?
Some interesting points brought up by aexiel as far as the Metahumans are concerned. What in the hell made these guys be so drawn to becoming 'heroes' the average person whether they live in a world with magic or light speed travelling spacecraft they aren't all that prone to just becoming 'heroes.' I mean these Metahumans are still people right? In general the sort of fantasy hero, which then evolves into a super hero in a more modern setting (Which is what I'm assuming here) typically there is motivation from the individuals not just a genetic instinct, A pretty straight forward answer (If it does have to do with the group) is usually they're creations of whatever deity is around in the world (Which by the way you open your description makes me think this may be the case), for instance within Christian mythology the Angels, God's soldiers are pretty much heroes who were built for that express purpose of kicking demonic and fallen angel ass.
If they aren't divine demi-gods or something akin to the Amazons, I am curious as to how the Metahumans came to be the way they are.
To use another example from my own world, the sort of heroic type group/race (And by heroic I mean they're the best soldiers in their home nation) The Haragladians are an old race which now resides in one of the most powerful empire's in my world. Originally they had their own kingdom which their race was the dominant group of the populace, but through some incredibly bloody wars in the middle ages the Haragladian race was cut to ribbons and the few that survived came out with a hardcore, Spartan-like subculture. They live and breath to serve their Emperor, they're about as heroic as you can get and have some superhuman capabilities as well (It's what makes them such great warriors.) So now when you get to the modern day, the tiny group of Haragladians that remain are born and raised on the tales of their forefathers fighting and dying for their country as heroes of the Empire, and they get groomed by their culture to follow in their footsteps becoming soldiers themselves.
Moving on, what sort of government are we looking at for this nation, is this an empire, a republic? The innerworkings of the Taskforce can make for a formidable world all on its own and an interesting and intriguing one for your characters to navigate at that.
I could rattle off more but I don't want to overload your brain with too many questions. I look forward to seeing this world unfold and develop, and I look forward even more to the stories you discover within that world, it's pretty kickass. Though I would warn you that you may get bogged down with a lot of ideas if your not careful. (Definitely not speaking from experience there, heh heh heh...)