Interestingly, and please keep in mind that I do not now, nor have I ever (yet!!!) owned a horse that is simply MINE.., I do actually tend to like or prefer (for whatever that is worth) a face/head that is unusual looking!
Nothing about a horse's looks is going to make or break him/her for me (not speaking conformation, just color, "looks", things which won't effect performance or health, but are merely aesthetic in nature), facial or otherwise.
I do feel a kind eye can go a long way, but that doesn't mean the eye has to be large, brown, liquid looking...it can be blue with or without eyeliner, smaller yet open, observant, or just have a "look" in it that bespeaks kindness.
I'd have to see the face...I like a lot of white on the face, so that may seem fickle, but I feel it brings interest to the features...otherwise, so long as he/she is healthy, of a conformation not to cause problems for certain given the sort of riding I'm interested in doing, and fits ME size-wise (doesn't make me look too big or "too" puney--with my Über-short legs, it's nice if they are able to "drape" if even a bit, down horse's barrel, as to at least make it feel/and look, to some extent, that I can wrap my leg around the horse, if even somewhat (!), that is a nice thing!)
But if the horse and I connect, I feel it might make me a bit more partial to said horse if he did have a "less than gorgeous" head! That's probably weird, and may have something to do with my aptitude toward the underdog in all things...hmmm. Something to consider!
"I'm too busy working on my own grass to notice if yours is greener"