Hm, good question on the colour scheme, they look a bit dull without some kind of defining colour for the faction. All they need is a splash of colour, look at the Valkyrie faction. They used to have no defining red colour stripes on them. They looked quite boring and dull, with a splash of red on them they became quite appealing and interesting. Maybe put some blue stripes on them to liven them up.
I noticed on the largest ship that the turret mounts on the flanks don't blend well with the inclining edges that lead to the top of the ship. I think that the beveled edge should have a curvature away from the turret mounts so it looks like they're part of the ship rather than sitting on top of the ship sprite.
Otherwise, well done, looking forward to the development of this faction.