Separate colour silhouettes or some other identifier for each npc class. Relying on the movement number isn't intuitive.
I'm not sure I understand, because the three NPC classes already have 3 distinct icons (the soldier looks like he's throwing a punch, the scout looks like he's running, and the skirmisher... well, doesn't look like he's throwing a punch or running). Does it need more than that?
Until you just pointed this out now, I had not realized there was a difference at all.