This is an idea I proposed a long time ago, in the early days of Demigod Beta (I think I brought it up in IRC, to Scathis...that's how long it was.) Anyway, the point is to give Demigods further unique identity, separating their different goals through their Passive Skill at the bottom.
Each skill should give a different bonus based on the different Demigod, in addition to the traditional stats. An example would be an inherent crit chance for Regulus, inherent life drain for Erebus, bonus to all allied healing for Sedna... et cetera. I'm not here to determine the specifics of each skill, simply to propose the idea.
This idea would allow each Demigod to gain a stat or attribute that is beneficial to their intended roles in a battle, and allow some of the "weaker" demigods to gain bonuses that could help them gain use from players by giving them bonuses that would make up for their current weaknesses.