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The slow speed is walk - hence "walk on" to start. It has a distinct four beats if you have coconut halves. The bottom mid horse looks right. Horses walking is correct though marching implies some synchronisation. The trot, the next speed, is reasonably comfortable for the horse but less so for the inexperienced rider hence the need to "post". Trot and walk look similar in the horse figure. Canter (3 beats) and gallop (4 beats) also look similar in the horse figure. The rider looks different in all four gaits. At the gallop the rider usually leans over the neck of the horse. At trot the rider "posts" as opposed to sitting in the saddle at walk. Canter - the rider is usually high in the saddle.
Most of the human figures in set 070 look absolutely right for a walking horse which they will have to share. The problem is that the one walking horse repeated 8-12 times will ruin the realism a bit as they will look as if they are synchronised (left right, left, right).
In future Strelets ought to consider the horse poses if they are to be used in several sets eg 3 walk/trot and 3 canter/gallop. The static pose could replace a walk/trot pose.