With the smaller factions you need to make much use of your FMs. The Pontic and Armenian bodyguards are insanly strong Kinsmen cavalry. Four or five units of them set up in a block (not a thin line) will exterminate a full unit of Hypaspistai or Thorakitai Agematos Basilikou, what is by far the strongest the Seleucids can field, with one charge by own losses of two or three men. The same horsemen are able to break a unit Agryiaspides, frontal and uphill if necessary!, - by higher casualties of course.