These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Angst? What Angst?: Though this is the first time Clain has witnessed people getting killed in Episode 3, Clain is only mildly bothered by the events of the previous episode and quickly regains his composure in Episode 4.
Moral Event Horizon: Pretty much everyone hatesBarrot for attempting to force a virginity check on Phryne and wants him dead for embracing/fondling Phryne and licking her cheek in front of Clain and Nessa, no less.
Nessa in Episode 4 when it appears Clain accidentally leaves her behind. Subverted in that Nessa turns up on the Lost Millennium airship in Episode 5, and she easily gets over her disappointment in Clain and her anger towards Phryne during a game of hide-and-seek.
Phryne, Phryne, Phryne. She almost gets raped by Gail in Episode 7, and who knows how long her father-like figure Barrot has been acting all touchy-feely around her and just what exactly he has been doing to her prior to her escaping the temple.
Clain = Jean: Clain obsesses over outdated tech and gadgets, similar to how Jean is into technology and his inventions. Both fall in love with the mysterious heroineat first sight, and eventually forms a trio with a younger child character (Nessa/Marie). And both of their fathers die.
Phryne = Nadia: Mysterious female lead, who's being pursued by an quirky trio (Enri and Co./the Grandis gang), because she has the MacGuffin they're after (Nessa/The Blue Water). They're both broken birds, who continually push others away, when they try to help them, and take time to thaw. And both turn out to be more than they initially seem ("The Key"/an Atlantian).
Nessa = Marie: Both are child characters, looked after by the two older characters of the trio, and thus, form a familial unit.
Enri, Butcher, and Tamaki = Grandis, Hanson, and Sanson respectively, and share virtually the same role. Like the Grandis gang, they eventually befriend Clain and Phryne to battle their eventual mutual enemy (The Temple/Neo Atlanta). The only difference is Enri developes a crush on Clain, whereas Grandis fell for Nemo.
Similarities with Skies of Arcadia: Let's start with the obvious: airships. The Temple has 'em, Lost Millenium has 'em, they're everywhere. And, since LM is at odds with The Temple, ship-to-ship combat (no, not THAT kind) is a given.
The scene where the different factions of LM band together for the assualt on the Temple is very reminiscent of the Blue Rouges and Black Pirates joining forces to battle the Hydra Fortress.
There's also the scene where Enri and her gang pursue Phryne, near the beginning of the first episode, which plays out similarly to how Alfonso disabled Fina's ship, in order to capture her.
Not to mention, the similarities between Phryne and Fina. Both are mysterious, each is being pursued for a secret they possess, which happens to be the key to their world's future: Nessa, the other half of "The Key", which is needed to reboot the Fractale system/knowledge of the Moon Crystals' whereabouts, which can either save Arcadia, or doom it to destruction.