Blizzard passed another developer Q&A along to fansites, which included a couple hunter-specific questions. The one of most interest is that they confirmed there are no current plans to add more stable slots for hunters.
While I have all the slots I need, I totally understand the frustration of hunters who enjoy collecting the various pet taming challenges — there are after all more of these pets than there are stable slots. You put rare or difficult to get pets in the game and you gotta expect your players to want to collect them. And when they want space to put them this isn’t a problem — it’s a sign of a successful design! So let pet collecting hunters keep their trophies!
Q: Hunters are really excited about the new pets being introduced in 5.1. Requests have been coming in from both forums & social media asking if we can expand the number of stable slots so they can collect them, rather than agonize over which pet they want to release to free up a slot. Suggestions include adding more stable slots, or adding a hunter pet tab similar to the way mounts/battle pets are listed. Are there any plans for updating Hunter pet storage?
A: Not at this time. We understand the concern and are exploring options to better optimize the system, but the hunter essence wasn’t designed to be “catch them all.”
Q: Hunters are upset that Scattershot can be dodged, while Blind is on a 1-minute cooldown but can’t be dodged. What’s to be made of the disparity?
A: Hunters and Rogues have completely different toolsets that complement each other differently. Making side-by-side comparisons between class abilities is a good way to become needlessly frustrated. Scattershot behaves the way it does by design; it is a ranged attack and intentionally subject to being dodged.