The snout issue is like one of those annoying perspective problems you can spend hours staring at and pushing paint around trying to fix. I hate those!
I tried after you first posted it and went for moving the snout round slightly, but found I lost some the original shape in the process.
Sineater mentioned the ear - if you draw some perspective lines it seems to be out of line a bit.
As you’re reinterpreting a flat design into 3D, maybe try turning the mane into more of a nebula cloud as it moves away from the head? I think that would be in keeping with the original design, and you wouldn’t need a background to make that look effective.
One thing I really like in the references is the expressiveness of the character. That’s obviously easier to pull off in a 2D cartoon, but maybe tweaking the expression in your drawing would elevate it further? It’s something I’ve often neglected in my own work - but I’ve become acutely aware of it since trying to do comics.
Overall it’s looking good so far though - nice work on the values!