From an artist point of view, #1 is absolutely spectacular. .. the scenery and lighting couldn't be more perfect and dramatic. .. However, from a horseman point of view, to make a better "horse portrait" (and to show conformation), you'd want the horse more squared up and balanced better . .. I hope you shot a few more of this horse in this location. (a lot more, actually.. it was perfect lighting - perfect location for this gray)
The head shot of Savannah is nice .. but (darn it) - where are those ears? The grazing shot is a no-go because your eye is drawn to the out of focus horse, not the one seen in the background. (might have been different if it were the gray horse). The eye shot is nice.. and I'm sure the owner will be pleased.. You could PS the lead rope out of the action shot of Savanah. .. The lighting couldn't be more perfect on her head and gorgeous mane. .. but I wouldn't use it as a conformation shot. .. I dunno.. maybe it's the way she's moving but it makes her look quite thin. (is she a TWH? ).
The location is spectacular. Shooting at that time of day is perfect for the location. (early morning or late day being the best time to shoot horses and/or to shoot for dramatic lighting) You did a GREAT job for your first horse shoot.
One thing I've found when I do ranch calls is that it's easy to have too many projects and too many horses. Yes, it *can* be done .. but the selection of stellar shots is often compromised. I try to limit myself to one, two or three projects. (but that's me. .. especially since I suffered heat exhaustion after the last 4 hr ranch call... not fun w/full body cramps)