it may seem strange but playing with the KH and Baktria I didn't felt the need for thureophoroi or thorakithai except in provinces that can't recruit top phalanxes. Bot units look too much "average" too me. What I mean is, they are not classic lineholders nor barbaric close-combat fighters. So I prefer a combination of hoplitai and/or phalanxes flanked by ie Thrakioi Romphaiophoroi (I conquered practically all of Epeiros with the KH using this). With the Baktrians I used pezethairoi/kleruchoi in the center and whatever infantry I could recruit on the flanks (eastern axemen were awesome!). Personally I can see why thureophoroi and thorakitai were not widely deployed by hellenic armies, and I also can see why the Romans called them "imitations"... they were not actual imitations, but indeed they are like less powerful roman infantry. Just my opinion :)