Not what sign they are but what sign they should be, based on their character traits.
I recently read through a zodiac sign book when i realised that one or two of the signs fit certain LOSH characters very well. For instance Lightning Lad SO fits the desc for an Aries (with some traits from Leo as well) IMO. So what do you think? Do you have any thoughts on what Zodiac sign the different Legionnares and villains act like?