Okay, the reveal of the princess’ secret identity was a good twist. No question there, but... it really should’ve happened in the second episode.
It’s worth bringing up CODE GEASS as a comparison point here. That show was also a mecha sci-fi that involved prep schools kids having to take arms against a hostile government, and it also involved pampered royals causing problems once they got involved on the front lines.
The major issue with CODE GEASS was that - - as Sam would put it - - it packed its premise with too many ‘buys.’ However, while the world-building got a little complicated, too quickly, the plot always had a strong through-line. There was a clearly-established protagonist, leading a cast of clearly-differentiated characters, who all received clear intros.
ALDNOAH is just as top heavy with lore as CODE GEASS, but it’s collapsing under that weight a lot worse because it never bothered to introduce its characters properly. I can’t tell any of these preps apart, because their first scenes were just scenes, not introductions. Same goes for the martian villains. The only character I can really identify here is the princess (she’s like the Lelouch of this plot!) because - - guess what? - - she got an actual introduction in episode #1.
Observing this, I think I’ve finally gained a better understanding about why anime became so infamous for characters with ridiculous colored hair. Give a character a bright, green dye job and - - guess what? - - she’s going to be a lot easier to differentiate from the rest of the cast.
So yeah, I say this twist should’ve come during the second episode, because it would’ve more solidly defined the princess as the lead (right? Like Lelouch?), and we'd be introduced to the rest of this complicated world through her eyes. That'd be solider plotting. Instead, it’s just a bunch of made-up politics and lore, presuming that we should tell these characters apart because we can read the crew’s minds.