What Do You Think of This Query for My YA Fantasy?

As many of you know, my agent medically retired toward the beginning of last year. I'd already been struggling to come up with my next project, and this setback didn't help. Gladly, #PitchMe came along, which gave me time to plot and plan. I wrote and revised a PB as soon as #PitchMe was done, then started working on a YA I'd been pondering for months. I've nearly finished the first draft, so now I'm just starting to think about how to pitch this project. It's still several months away from being ready to query, but I would love to get your thoughts on my query in the meantime. This is only the first draft, so I'm open to all feedback:

Dear [Agent]:

As the adopted son of the highest high chief of the Lands, Almundemba’s never felt like he actually belongs. He’s too pale, too paranoid, and more interested in plants than in governing the Lands. But Almund has one use for his political cachet, and that’s to alter the Exchange. For too long, this exercise of trading children like kukuis has benefitted his birth country more than his adopted one; he wants to rebalance the scales.

Relentless as the Tide used to be the only child of the highest high chief of the Lands—until he traded her for the Homish sovereign’s newborn when Relentless was a toddler. Twelve and seven years later, Relentless finally figures out why her adopted mother willingly Exchanged her son: because she needed a daughter to pledge marriage to the heir of her country’s vengeful neighbor. Relentless wants no part of this and hijacks the steamer bound for the Lands and the Exchange to abolish it for good.

This won’t be easy, though. The highest high chief of the Lands doesn’t wish to void the treaty that has kept his nation safe, and Almund has his own agenda. Luckily, Relentless has one more bargaining chip: a biological half sister who resembles her a lot. Setting her principles aside, Relentless kidnaps her half sister to pledge marriage in her place.

When Almund learns they’ve disappeared, he vows to bring his sister back. She’s the heir their country needs. But sisters have minds of their own, and this one has other plans. Now Almund must convince her she requires rescuing before she marries a monster—and he’ll need Relentless’s help.

[TITLE] is a 100,000-word fantasy for young adults inspired by h­ānai, the traditional Hawaiian practice of informally adopting children to bolster alliances. After my previous agent medically retired last year, I spent the next several months formulating the right project with which to secure a new one. This manuscript is that right project and has never been submitted.

Like my main characters, I was adopted as an infant. I’m also part Hawaiian and the author of four middle grade novels, including THE SOUND OF LIFE AND EVERYTHING (Putnam 2015) and THE MULTIPLYING MYSTERIES OF MOUNT TEN (Bloomsbury 2019).

Thank you for your time and especially your consideration.