I do think this comment, by River, is on point:
Maggie Stiefvater’s writing style was essential to the tone of the series. I can’t see that translating well on television.
Personally, though I enjoyed Cabeswater immensely, it is the characters I think about when anyone brings up the series. They are so precious to me that any cast will inevitably disappoint me.
I feel like I am being a Negative Nancy here but I can’t stress enough how big a role the author’s particular writing played in why the series is so loved.
It is indeed Stiefvater’s beautiful writing that hooked me. No question about it. And she puts us in the heads of her characters, always a challenge for visual media. Also, I have a really clear picture of Ronan. Not so much of the others. But I could see casting either working for me or totally not working for me depending on the actor cast as Ronan.
Still, I will be very interested to see how a miniseries is handled.