#1

Rule of thirds

Striking eyes

Good color

Foreground hot & out of focus

Good natural color

#4 

Sky overexposed

Too dark on horse

Alert expression

Composition good

About to walk out of the picture

Soft focus

#3

Good composition

Good head turned

Good line of the leg

Cut foot off

Grainy, blown up too much

Over enlarged

#2

Sky is a nice color contrast

Horizon in good place

Edge mergers

Centered