I really hope the princess (the twin sister, not the girl with the blue hair) becomes more of a major character. She is clearly important, has a network of spies, is supporting her brother, and honestly doing most of the work to make sure that they’re okay. She is clearly making large portions of the plot move, and I hope we see more of her.
Also...she’s really hot. And charismatic. The prince has no charisma and is kind of...aimlessly murderous. The princess is intimidating but always seems to have a plan, while the prince just reacts (usually badly).