Morpholgy? Is the Solarion supposed to have full slots? If not, may repropose to doing him as a reddish star? You can use the star from this pic as base (
http://xs539.xs.to/xs539/09201/modspritedump1563.png ). I have noticed that the star graphic works especially well on ethereal troops (since the borders keep on disappearing, making it seem like it is pulsing)
Hmm. I just got an idea concerning the watermaiden, you know, to flesh her backround up a bit. Feel free to scrap it if you don't like it.
"Cocytys (spelling?) and Inferno are filled to brim with horrible demons hellbent on devouring and enslaving the humans. The ground is full of spirits and their longdead corpses, who are just waiting to get their conceived revenge on the fleshlings above. Pantakrator knew this of these dangers all too well and thus placed powerful blessing on all living creatures. Whenever tears are shed for those who have lost their loved ones to a profane menace, they will not just disappear. Turning to invisble mist, the tears will travel to skies and form watermaidens. They are the living vengeful memory of those fallen before the unholy ones, and will purge them from the face of the earth. They take the form of [whatever] and can [description of powers]"
So yeah, the main idea is them to sort of "tear" elementals. If the description gets too long, you can sort of.. divide it between the summoning spell and the unit itself (the summoning spell could explain more backround, while the power descriptions coud be left for the unit itself)