DAve, i don't have a tablet so doing a red line for you is neigh impossible, i tried.
Instead i did the next best ting, i thought that possibly if part of your last image, and a reference image from Jake Sully ( jays challenge forum pic form the first post he made) Namely to start, the nose's of both were side by side you might be able to see better.

Notice yours the septum falls low very human like on the nose.
Where as Jake's septum is almost square with the botom of the nose, a very subtle difference that woudl add a slight angle to the nostril plane on his nose, but not very much of one.


The next part, i think you are very close with the width of the nose, the top edge of it along the length...
But i believe it is too round, you need to flatten it out more, again see the Jake sully nose posted in the attached image right below your last update's nose.
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also notice how the bridge of the nose doesn't thin down like human nose would, it fans out and integrates its self into the bulge of the brow bone.
I'd almost get the image of like a bone shield forming over the tear duct the way the bridge of the nose fans out, if i didn't know better then it being that way, if that makes sense?.. like a swooping curve down form the brow bone, strait into the squared off sides of the nose.

Gah, i need a new tablet, much easier to show you with red lines. its just impossible to do with a trackball, for me anyway.
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hope this helps.
G-man