Urgh, I understand about the whole head thing, the neck was also a big pain to me as well. No matter how much I tried, it just never looked right D<! Ah, I never knew that about the head shape and all, well, I knew they were different but I didn't realise how different, so thanks! I'm still trying to figure how what breed of horse she should be, she's not a draft kind of horse, but she's not exactly an Arabian'like horse either (in my mind, anyways xD).
To be honest, I didn't realize horse heads could be so different until I was researching Shire horse anatomy for an art project (to this day Shire horses are probably the easiest horse for me to draw because of that art project). You learn something new every day.