I was going to post this as soon as I saw it the other day, but you beat me to it (stopped by earlier but didn't get a chance to reply). While I do love the actors in the film, yes as you mention, there is the issue of the image of any of the Prophets (peace be upon them all). Though a part of me does wish that we could somehow see the events that shape our faith (again, as you said, the narratives differ in both Prophet Nuh's case and several others of course). Those who know me, know I have a thing for Emma Watson lol. Loved her in HP and Perks of Being a Wallflower.
Anyways, I do admit I want to see it, religious issues aside, just as a film on it's own. So please don't get mad at me hehe.
But yeah, as you said, when films or documentaries like this come up, it's a chance to at least tell the story from our tradition, as it is bound to come up in a mature discussion of the topic.
Just my thoughts.