My comments:
I view the Resistance, and the First Order, as paramilitary organizations (like guerillas). The central government does not have a firm control of the situation.
agreed. IMHO I think they wanted to have a black character to appeal to black moviegoers (pardon my candor) and he kind of sticks out and doesn't fit into the situation.
3,6,7. OK. OTOH, you might say similar things about Luke Skywalker in the original Star Wars - a simple hayseed farm boy, walking straight into a galactic war and triumphing. In Rey's defense, Rey was a plucky, independent and resourceful person forced to live by her wits for years.
4,5. Kylo is out of control, immature, and undisciplined. He is not fully trained. He admits this to whatshisname, that giant hologram guy ('complete my training' or whatever he said). So 4,5 to me are plausible. His mask... well lots of characters in the Star Wars universe wear funky masks and headgear. In his case he's trying to emulate and connect with Darth Vader. Another evidence of his immaturity. Also a helmet can offer head protection.
Yes. Better to resist and die fighting, that to submit and lower the shields. Automatic death sentence. However when you look at Kylo or Finn, you see evidence of a lack of single-minded devotion to their cause. I suppose with Phasma it's similar, she(?) is not willing to die pointlessly for the cause. But like #9, she expressed that lowering the shields won't change anything, like Grand Moff Tarkin expressing disbelief the Death Star could be destroyed. So maybe she figured, whatever, I can lower them, that's fine you go ahead and attack, just see what happens.
I suppose it's like the Titanic, it's engineered so well that the idea of an attack is implausible. We have shields, why do we need a defense against x-wings? We have stormtroopers, how could anyone infiltrate and shut them down? Even so, we're the hardest-core military force in the galaxy, what could go wrong?
I think they wanted to reach back and re-connect with the original trilogy, in a way that made fans happy. I'm OK with this :)