Nice compillation so far.

Yes, the most striking aspect is the sexual dimorphism but if we think about it, however racist it might seem, they are likely half dragon, and sometimes there are even greater size differences between sexes in the animal kingdom.

Their dragon-ness might explain the eyes as well. It makes them look like they are constantly dreaming, as if they were on a totally different level spiritually (think Sephiroth in Advent Children).

As for Yugiri, I'm pretty sure her face will be totally unique. Central characters are always unique.