Its really hard for me to pick. Your sets all work so well. The colors are varied yet comfortable. The ships are logical expansions (such as small escort, slightly improved frigate, and so on), and things look like what they are (mines, satelites, drones, fighters, etc). So much variety yet so much logical design in all of them.
How about if I say that 90% of anything you do is my favorites and the only part which tends to turn me away, if at all, are some of the portraits?
Of course I could make it worse. Ive been thinking that Id like to ask for a set so I could design the race description around the way I play, then put a pic of me in the portrait. (hey before anyone groans... wouldnt you love to come across me in the game so you could... ummmm... respond to my presence?)
