Q. How are you trying to separate the play styles of the hunter specializations? What makes Cobra Shot feel different from Steady Shot?
A. Cobra Shot is ideal for Beast Mastery and Survival hunters because they don’t really have any other way of keeping Serpent Sting up (Cobra Shot extends Serpent Sting’s duration), and also for Survival because it is “Elemental” damage. It's also useful in PvP or in some other niche situations, say, when a creature is immune to physical damage. Now you have a solution.