Okay, I've been looking over it for a while now and I think I have a few more suggestions!
Alright. First off the hooves are a little too pointed. In the picture, his hooves are a lot straighter, like a column instead of a slope.
The mane looks a little too pronounced, but I don't think it's that big of an issue honestly.
There's also a bit of a ridge around the base of the horns, and I don't know if you wanted to add all three spheres to his head or let the texture take care of that.
Finally, the tails should be straight all the way back, yours taper a little. Again, I don't see it as an issue but if you want to make it as close to the image as possible, I hope you take these into consideration!
For the record I really like this model. I like how it's still kind of angled and geometric looking, it fits with the whole minecraft thing without being overly blocky. You're really good at getting the shapes easily visible without making it ridiculously smooth. Good luck on your other models!