Hey !
My new WIP :
For the moment, i model just the " head"
Thanks for future comments
Hey, nice skull! I tried one myself one time ago, and I know how hard it is…
I think in relation to the Eyes the “nose” is to big or contrariwise…
Further I the Eye-holes should go more inside… And there’s something wrong whith the jaw-bone under the theeths! not sure if you understand what i mean… But on this image you maybe can see what I mean:
Let me start with saying that you are doing a great job.
But I guess the reason you posted it in here is that you want constructive criticism. So here goes:
In the front view the top of the skull looks too pointy.
The maxilla (upper jaw) looks like it is a seperate object and stands a bit out.
The teeths are too far apart (I guess that is because you only have 24 teeth in the jaws, instead of the normal 32).
I hope those comments are of some help to you. But don’t forget that you are doing a great job.
nice work,i love skulls,i like the design and the way you modeled this,has a nice stylized character look.
only thing that is bothering me,is the jaw.
Thanks all for the comments.
I guess the reason you posted it in here is that you want constructive criticism
Yes it is 
For the teeth, i have arrange this (there was less of the reality, it is normal)
For the top of the skull, i’m going to modify this error, and for the jaw too.
now is my turn - teeth are terrible -part of them should be in the upper part of skull - they don’t grow up with the skull they grow up inside it.
The ‘eyes’ they look too flat - the eye holes should be placed a bit deeper
Add tthe last one - barier in the nose is made mostly of cartilage and is smaller.
You can look on my skeleton model 
You can find it here :https://blenderartists.org/forum/viewtopic.php?p=404462#404462
Pfuu, it was a long time that I blend 
(this time which past too quickly)
The update :
Thanks for all comments
Wow, thats much better. Don’t forget that the cainine teeth are supposed to be pointy
Nice - maybe model isn’t anathomically correct but i like it. The skull is much better. I’m looking forward to some more renderings 
I have not very full time to blend, this explicate my slowness. In think that the final modelisation of my skeleton, due to the fact that my pc saturate a little, ; that in the final scene, skeleton will not on the foreground ; and that i’m going to work for the A-level (!!!)
The image :
In the final scene, the skeleton will have got my concept gun, and this scene is going to intitulate “Definitly dead”
Thanks for all comments