I really like the idea of the spiky halo, I think it gives the character a more identifiable silhouette, though it could get confusing if there are other angels that look similar.
As for Rowen I like the ponytail (big surprise) and the cape. Specifically the ponytail I think helps make him easily identifiable, such is the case I recognize him from the previous piece where he is attacked by the magic attack, simply cause he had the ponytail there too.
For character designs, other than having them look cool (which they do), I think it's important to see how they fare when grouped together to see if you can easily distinguish them even under unusual circunstances (only by their shadows, when in movement, from different angles, etc).
It'll be interesting to see more of these!
