Some points:
Decrease the field of view of your renderings to 15 degrees or less. Anything more than that is useless for evaluation and comparison to existing horse photos.
Arabian horses have one less vertebrae than other horses, and thus a shorter body. Decide beforehand what you’re trying to model and use the appropriate references.
The lower parts of both front and back legs are too narrow front to back.
The ears are too narrow front to back at the base.
The lower front part of the cheek is not right.
The croup is not right.
The tail is too thin.
The profile of the rear underside is not right.
The general profile of the head needs improvement.
The facial crest should not swoop down at the front.
Other than that, it’s looking pretty good.