Feedback Request

You critiqued my query here with Facelift 1304 and then did a feedback request here. I've taken some time away from querying this book to come back with fresh eyes, so hopefully that's improved the query.
Also, as I'm sure some of your commentors will be happy to hear, I have changed the working title of my book.

QUERY REVISION:
Eric Ortega doesn't know it yet, but hybrid creatures with magical powers live hidden in his world. The winged Sentinels police the hybrids, keeping them from discovery and protecting the vulnerable. [From the hybrids? Who are the vulnerable, and what do the hybrids want with them?] The Sentinels are after Nikias, a human-wind hybrid who can control the winds and weather and only has a body when he steals one.

When Nikias takes over [possesses? hijacks?] Eric's body, the Sentinels snatch him. Eric wakes up in the Sentinel's [Sentinels'] tower, missing half his memories. The Sentinels failed to trap Nikias. Instead they've got a human who knows too much about their world.
Eric's had enough of this. He wants out, he wants home, and he wants all his memories back, thank you very much. The problem: Nikias imprinted his powers on Eric's mind and body. [Not clear why that's a problem. I wouldn't mind suddenly having the power to control the weather.] The Sentinels tried to erase them and aren't sure if it worked.
It didn't, but Eric's keeping that under wraps. He's less than impressed by these Sentinels. He told them Nikias threatened his family. Just because he doesn't actually remember his family doesn't mean the threat isn't real. [A more effective ending would be telling us what Eric plans to do now that he has Nikias's power. Using it to hunt down Nikias? To destroy all hybrids? To expose the Sentinels? To save the family he doesn't remember? What's his goal?] 
Complete at 66,000 words, THE STORM SUMMONER is an upper middle grade contemporary fantasy that features diverse characters. [Until you say this is a middle grade book, a reader could easily assume Eric's an adult. Tell us his age when you introduce him.] I hope it will appeal to fans of The Underland Chronicles, Museum of Thieves, and Savvy.
Sincerely,


Notes

It's an improvement, but I'm not sure your story doesn't start where your query ends. If you had to summarize the book in one sentence, would it be: When a demon [accidentally?] gives fourteen-year-old Eric Ortega the power to control the weather, he decides to use this gift to . . . ? Finish the sentence. You spend most of the query telling us how Eric got the power he will use to accomplish his goal, but what's his goal? What's at stake? What's his plan?

You don't make it clear that the hybrid creatures are all evil (are they?). Does anyone know the hybrid creatures exist? Do humans know the winged Sentinels exist? Seems like if they fly and have a tower, we'd know about them. What would happen if the Sentinels weren't policing the hybrids? In other words, what is the goal of the hybrids? To take over the world, destroying humanity? To have a country where they can live in peace? To kill random people because it's fun?

I don't think you lose anything by leaving out the Sentinels' wings and leaving out the term "hybrid." The hybrids can just be creatures with magical powers, and Nikias can be a creature who can control the weather. Calling him a human-wind hybrid isn't helping. Maybe you should call them demons if they have the power to possess humans. Then you have a wind demon, a fire demon, a water demon, etc.