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.
Also "Servants of Fire". Especially when it plays during Takemikazuchi's big reveal.
The Morricone-esque score as Rio and Kanata are walking through the town in episode 10, which is itself a stripped-down version of “Servantes Du Feu”.
Dissimile: This series is just like that other comedy series about a high-school music band, except it is not a comedy, there is no music band and they are in the military.
Might be considered also an inversion of the anime Full Metal Panic! and its first two seasons, with typically peppy schoolgirl dramatics occurring during a war, while Fumoffu transplanted the war to the classroom with hilarious results.
Expy: The crew is often compared to K-On!'s cast, even with such puzzling matches as Noël = bleached Ritsu.
Fan Nickname: The series itself has been referred to as K-On! season 2 or Military K-On due to the similar art style and the fact they're both about anime girls playing instruments. Also called /k/-On from time to time (/k/ being 4chan's Weapons board). And War-On, and probably a whole host of other, similar names. Sadly, no one seems to be going for Guns-On...
'Grace' for the blond trumpeter in the flashback. Real name, Princess Iliya. (Incidentally, her name was in the credits for episode 1, but who reads those, amirite?)
"Tank-kun" for the Takemikazuchi.
AIJOU YUUJOU is actually titled "Girls, Be Ambitious".
Starting in episode 5, Kanata and Noël get in on the hand-holding as well.
Filicia has an interesting way of testing people's language skills:
You have really nice breasts, don't you? I'm rather fond of them. I wonder if it would be alright if I play with them for a bit? Would it be alright if I played with your entire body? —Just as I thought, you don't speak any Helvetian.
Earlier in the same episode, Noël stops A’isha from trying to attack her by groping her bare breast.
After the Grand Finale, Noël/A’isha is widely considered all but canon.
Japanese girls wearing German uniforms exploring a Japanese music school in a Spanish town full of French people celebrating Chinese New Year’s in Switzerland, shooting North African owls while piloting multi-legged, talking, demon slaying, cloakable, AMAZING GRACE SINGING, 500mm coil gun firing "son of the god of fire" supertanks from the future. (And variations thereof.)
Nightmare Fuel: The corpse of the nameless soldier in episode 7. Especially when he grins, telling Felicia to commit suicide. Even worse is that it's all Felicia's hallucination, so really, she nearly talks herself into dying.
Off Model: The animation quality of the series fluctuates. It is fairly good across the series, with several Animation Bumps for key moments (every Takemikazuchi is lovingly animated, for example), but in turn there are a few instances of budget saving tricks and not-so-good art and animation (Kureha's freeze-framed loss of balance in episode 3, to name one).
Tainted by the Preview: People had some choice words to say when the first animation artwork came out, revealing K-On!'s art style, instead of Mei Kishida's original concept art◊.
Others got tainted by the credits roll. A series by the guy who directed Elfen Lied and written by the author of MAI-HIME suggested a certain artisticdirection, and were dissapointed when it turned out they were only right about the Break the Cutie part.
