The thing is... the novel also fleshed a much more dramatic and painful irony
Spoiler for novels:
Basically, lots happened for Louise and Saito. various MEANINGFUL arguements (such like dying in honor and stuff). As Saito is fighting with louise in the Zero Fighter, they had to read colbert's instructions for the "secrets weapons" which look like... gimmicks
here lies the irony: Saito does not know that colbert died, and he is reading the letter, asking him about the war, the sacrifices, the sins. and even his wish to visit saito's world.
OTOH, the drama was much more hotblooded and meaningful, as Agnes discovered the truth only when Colbert was half dead, after his battle against menville.
Kirche won a lot of points, with her development, as she despised Colbert in fact.
And yes, Agnes wanted to finish colbert off, but the circumstances were hell more portrayed
thus, reading Saito with the letter is painful, as his hopes will be crushed as he will come back to the academy
I don't know if it can be considered as the worst (as Nanoha strikers is a utter fail in term of sequel too). But like I and Darknemo said, the war is completely unexistent.
so far, we saw the guys leaving on the battlefield (which we never saw to begin with). A small glimpse of Reconquista army. Few henrietta moments about the war (they even watered down her memories of wales, when she was with saito, etc).
Frankly, the amount of actions is ridiculously disproportioned, and we got many tasteless and repetitive "comedy", while this season "plot" should be much more serious and dramatic than season 1. (i don't mind the start, with EP1-2, but there is a limit, and they surely bypassed it for too long... episode 5 is enough to be extremely annoyed)
I don't have any "problem" (well... i "can" withstand this) with "changes" with the characters (as Siesta was supposed to be much more heartwarming, and henrietta, much more dramatic, Saito really GAR, and Louise conflicting herself... but no they demolished them as well.)
But at least... give us the
PLOT, for Crying out loud!
EDIT, Mist : i don't know about if they should. But there is no way they can wrap a "war" of this scale in only 3 mere episodes. Heck, if they don't pull the 1/70.000 it will be FLAT.