I bought this model a while back as it's one of my favourite FW models of all time. I basecoated it, then put it away because I really wanted to consider what I wanted to achieve with the painting. My 1st thought was (near enough) precisely what you have done here - which is why I gave an 8, and not a 9 or 10.
For me, a 9 or 10 needs something different - whether it's a painting technique or contrast that really makes it 'pop', a well studied paint job that takes elements from real life sources, or some extra sculpting/customization that I have never seen before.
Having said that, I have downloaded this image into my research folder, and will use it as a sort of base. My 1st thought led me to buy some matt black pigment, which I want to apply around the mouth area to indicate ash... it may or may not work as intended. Melted flight bases (the transarent ones) work great to show 'drool', so I may do that. I also want to follow the 'fluff', so I think I will add more purples to the paint job to show that Elspeth's dragon is a little more long in the tooth. And unfortunately my cat ate one of the claws, so my hand is forced into doing some custom sculpting.
I think it's a stellar piece, and really it's just my personal opinion that a 9 or 10 should have something just a little extra. Still, on my personal scoring scale - an 8=fantastic, so well done.
Despite the score, this is breathtakingly beautiful and a piece of art. I searched for a painted version of this forgeworld model here, and you did not disappoint in any way. this is wonderful. 10/10.