The only "proportional mishap" with the mare that I see is that her neck seems really thin. But, in the same respects, there are also horses with necks that look as that. (There's a young filly posted for sale here that has an oddly thin neck.)
Otherwise, I find it unbearably adorable! <3 I especially appreciate your attention to detail; hinting to fur texture without over-doing it.
I love your shading and details. Those horses have such definition. It kind of reminds me of some of Joe Andoe's recent paintings. : D
Thanks! I've not heard of him, but I like his work! :)
Thanks Creampuff! You could be right about the neck. I'll post the reference photo so you can see where I was coming from. I appreciate the input because horses are very difficult for me and I'm always looking for ways to improve.
Well if you would like, you can PM me for critique whenever you would like. I also have access to a plethora of tutorials and other resources (including free-to-use stock images of horses) that I can refer you to. I'll be more than happy to help!