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?: Pacifica certainly has the right to crippling depression, considering her circumstances, but she's fairly upbeat, although later in the series she becomes a little more pensive.
Black Hole Sue: Cz could possibly be considered an in-universe example during her introduction, where Shannon suddenly takes a liking to a mysterious orphan girl and constantly dotes on her to the point of ignoring Pacifica and even driving her away when she protests. It turns out that Cz was secretly controlling him, though even after he makes peace with Pacifica again and Cz's status as a Peacemaker is revealed, he still remains close to her.
Complete Monster: Steyr is a Peacemaker of Mauser, a god who uses a set of ironclad laws to control humanity and keep it from self-destruction. Steyr, however, ignores her duties as a caretaker for mankind and instead tries to manipulate the rulers of the country most loyal to Mauser into unwittingly setting up the one situation defined by Mauser's laws in which she would have a perfectly valid excuse to wipe 90% of humanity off the map. While she's affable enough to her fellow Peacemakers, she doesn't really seem to care when one of them dies, and she seems more angry that she has now inherited his duties. She shows absolutely no remorse when her manipulations pay off and she gleefully orders Socom, her more powerful partner and subordinate, to start killing, and the only reason she didn't try to wipe out all of humanity was because Mauser's laws prevented her from doing so.
They Wasted a Perfectly Good Character: Several of them, actually. The Obstinate Arrows and Luke Sturm were Demoted to Extra in the anime, and many fans of the anime were disappointed that they weren't explored further. Those familiar with the light novels were only angrier because they knew that there was more to the characters than what the anime showed.
When she pics up the wooden bath tablet and starts bawling her eyes out because subconsciously, she is grieving for the loss of her almost boyfriend Fulle/Furet.
Also when she meets her real mother just before her mother dies. She doesn't even know that it's her actual mother, nor can she see her. It seriously tugs on your heartstrings to see her crying out "Mother!" after her mom passes away.