I once saw an amazing Narnia project done using wood elf glade riders as the basis for centaurs with armour moulded on in the style of the films. They used wild cats and a rhino mixed in amongst them to complete the cavalry units.
For the faun infantry I think they used ungors as a base with head swaps and sculpted on armour, mixed in with some done with beastmen heads like the ram headed ones in the first film.
I think they used the original Lotr gw dwarf archers.
I thought about doing my own fauns at one point. since I'm not very skilled with sculpting in green stuff I was going to cut an armoured human and an ungor at the waist and use the ungor bottom half with the human top half.i was thinking Lotr gw Minas tirith Warriors since I have a tonne of them sitting unused.