Also, it is amazing that the TSAB manages to pull this off, I have seen people describe MGLN as a post-apocalyptic setting before.
It's about as post-apocalyptic as post-WW2 Europe, if the rest of the world didn't exist. Which... is pretty damn post-apocalyptic, to be honest.
It's actually
multiply post-apocalyptic. The Belkan unification wars are not the first, not the second, but the third time civilization nearly collapsed that we know of. First there was the fall (well, disappearance) of Al Hazard, in a cataclysmic dimensional rift; then, the fall of old Belka; and the unification wars honestly count as their own cataclysm, given elements such as the Book of Darkness and (likely) Mariposa being deployed.
The Unification Wars were a probably inevitable consequence of the way Old Belka fragmented, though. Which is, I suppose, yet another line of similarity I could draw.
The TSAB was formed, IIRC, in response to the collective militaries of all the major sides of that war -- what was left of them, after the equivalent of nuclear war followed up with
more nuclear war -- rebelling against their civilian masters and going "fuck this", with an extra helping of "never again" once the
other civilians got used to the new and relatively peaceful situation.
They were formed through a military coup, which explains a lot about them; notably, as far as we know they aren't in the least bit democratic. The leaders of the TSAB have military titles and commands, and the major, politically relevant families we learn about, are military families. The Harlaowns would be an example. Nanoha has tried her very best to avoid politics, but Hayate's position is an inherently political one, and she's been climbing pretty high in the ranks.
Democracy still exists, on a local level. Administered Planets are still mostly self-administrating, so long as they avoid breaking anything; the TSAB's official powers are probably infinite, but habitually stop at the stratosphere for anything but capturing dimensional criminals or dealing with Lost Logia -- which are the equivalent of nuclear mines, half the time. That's not to say that they can't override the locals when they feel like it. There was a minor conflict between Midchildan authorities and the TSAB in the middle of StrikerS, where Midchilda was completely swept aside the moment Hayate found a decent excuse.
It's a government of people, not of laws.
If you know anything about history, you'll know that this is a recipe for disaster. However, at the moment they're still idealistic and
in fact non-corrupt, with people who are, almost to a man, trying their hardest to do good work.
This is not unexpected. Disasters, so long as they're survivable in the immediate sense, always tend to bring out the best in people. The TSAB has been recovering from a near civilization-ending disaster for the last two generations, and are only now just starting to come out of that mode. They've patched up all the
really bad battle-damage, and should now start on the process of nation-building.
That's how things will go, if they're going to go well.
One could write a really good story about that, whether or not you think the eventual outcome will be good, but MGLN isn't that story. Neither, I think, is this.