Headscratchers / Horizon in the Middle of Nowhere

• Questions regarding power level in the series:
  • Why are the Armors of Deadly Sin considered important? The first time we see one in battle, it's badly outclassed by the Slicing Dragonfly spear. The Ao DS in question lets its user go fast, while the latter can One-Hit Kill something by catching its reflection and has a Semantic Superpower based on the word "cut". The person using the Armor loses the battle after spending the whole time on the defensive. And to make matters worse, the next time Slicing Dragonfly is used, it loses badly because basically anybody who practices Shinto slap something together that's better than that. So, by association, the Armors of Deadly Sin are already far weaker than what the main characters are capable of at the outset of the story.
  • How is the Far East subservient to the Testament Union, when the former seems to be more powerful militarily? By the end of episode 10, on top of what's been brought up in the first bullet, The Far East has been able to destroy a Union gunship after deflecting shots from it multiple times, destroyed a God of War, something that's supposed to be a major military asset with only two people, and the actual ground forces have the Far East holding their own against a formation ten times their size.
  • How did the Far East ever become subservient to the Testament Union? The latter lost their whole dimension. It's hard to say how many would be killed due to that, but it would have left any survivors dispossessed and without any kind of infrastructure. Meanwhile, the Far East are the ones who've actually made anything of any power and Shinto explicitly gives you the best magic in the series. The Far East should have been able to steamroll the Testament Union in the backstory.
• The page describes this series as Grey-and-Grey Morality. The Far East wants to A) be independent, B) save their friend, and C) prevent the apocalypse. Meanwhile, the Testament Union wants to... take over the Far East. Which they already took over. But they want it taken over even more. Inocensius has a stereotypically Obviously Evil designs with the personality to match, while his right-hand man is a Big Red Devil. Where's the grey here, exactly?