Greetings : )
First of all i'd like to say thank you for the great effort put into the pet aspect of the hunter class, not only we could never have so many pets but now they are all more or less useful with their ability, making us finally able to use a great array of pets and not be forced to rely only on one "best" family for various aspects of the game (Hello TBC Ravagers and Woltk Wolves).
While abilities are very well spred among pet families i'd like to suggest spreading them even further in cases where we find two families with the same talent tree sharing the very same ability.
Having the very same ability on multiple pets is a good thing but having these pets share the same talents basically make them clones just with a different skin, spreading the same abilities on another talent tree (like it's already done in some cases like the disarm on both a cunning and a tenacity pet etc) may bring us a greater choice for different situations (like in some cases bringing a ferocity pet would be better than a cunning and so on ) help us feel the pet "different" and actually allow more reason to keep two pets sharing the same ability.
Wind Serpents/Dragonhawks: both bring the magical damage debuff and both are cunning, while wind serpent are totally fine with the idea of them being cunning flying snakes i could totally see Dragonhawks, being fiery dragonlike bird creatures, switching to the ferocity tree.
Tallstriders/Foxes: both bring the thunderclap debuff and both are ferocity pets, i could obviously see Foxes switching to cunning, i mean what's more cunning than a cunning fox?!
Carrion Birds: Ok, these are actually fine since they are ferocity and share their ability with bears which are tenacity however i could see them switching to cunning since well...it makes more sense to me for them to have access to talents like Feeding frenzy, CARRION feeder and so on, not to mention that real life Crows, Ravens etc are well known to be very smart beasts.
Turtles/Beetles share the same ability and both are tenacity however they can be an exception and remain like they are since Shell Shield/Harden Carapace only helps tanking pets and i guess there are some infidels out there that may not truely understand what "Turtle Power" means and actually like more a tanking bug (Fools!).
Exotics sharing the same ability with various normal pets (Devilsaurs and wolves, spirit beasts and cats etc) are fine aswell as they already offer an additional unique ability and are available only to one hunter spec making them stand out on their own.
Now let's speak about something i'd love to see tameable...
It may be a redundant request but Stags/Talbuks/zhevras/Shoveltusks/Giraffes could be great as tameable beasts, they have great models and would be nothing to "far off" being normal beasts and nothing like undead/dragonkin/elemental creatures which may not be fit as tameable creatures.
They could probably all go under the same family, something like "Grazers", "Herbivores" or "Bucks" and i could totally see them as ferocity beasts, bringing some debuff like the +phisical damage (like ravagers, which are cunning) or increase bleed effects...however that would put them in the position of what hyenas are supposed to be at the moment although i think that heynas could very well switch to the Cunning branch because, like what i already said for carrion birds, in real life (despite what many people think) they are very intelligent beasts and having them gain access to talents like Feeding frenzy and Carrion feeder would probably fit well.
Now that we are talking about hyenas....please fix tendon rip

I posted already on the official forum sometime ago, while ravagers, carrion birds and the like had their abilities fixed hyenas still have their Tendon rip ability not working on bosses, probably because it kept something from when it was a snare in wotlk.
I just hope that someone is aware of this issue at blizzard since hyenas are pretty much the only family left with their ability not working
About new sknins for existing families...
Rhinos and Core Hounds have very few skins to choose from, would it be possible to have kodos/cleefhoofs join their northrend cousins? they look very similar and i think they could work with some tweak.
I'd also love to have at least some Core hounds with the Void Terror skin as tameable, even if they are very demon looking we already have one tameable drakeadon (Chromaggus!) which are usually classified as dragonkin so one Void Terror, even if just one mob in the entire azeroth, as tameable would be very well appreciated.
And last but not the least...Broken Tooth.
That one is a very legendary cat, sought by hunters of old for months before being forgotten, if possible i could totally see him having his very same skin upgraded to the riding skin model, that skin is already in the data and no cat is using it (yet), he would totally deserve it to make him stand out once again (even if just by looks!) among his normal cougar cousins.
Oh well...i realized i wrote alot and i'm sorry for that

Hoping someone may like my suggestion aswell, or at least some points of it!