Some thoughts. I have 5 hunters and I LOVE them. I love pet classes. I play defensively more than burst offense. Random thoughts.
I chose Draenei since the GotN is really nice heal for hunters or pets. I put it in a castsequence so I can put as many or as few as I want on a player/pet.
I have 2 sets of pets. PVE/PVP. PVE is now (I will skip the past ones), 3 bears (swipe, thunder, tenacity), 1 carrion (screech) and 1 worm (armor debuff should make melee pets and normal shots hit harder.
The PVP set is carrion (to tag people so you get HKs from them and never hurts to have annoying, flapping, loud pet in someone's face, hyena (hamstring), tallstrider (AOE tagging again mostly, but 1 free miss isnt so bad and nice to have a weird pet just for personality), core hound (slow casting is nice) and wasp (sting for rogues---no stealth). All ferocity.
Having 2 sets of pets lets you pick different talents like dash for PVP, but that is wasted in PVE. Increased is wasted in PVE, but better armor/healing is better for PVE (won't help in PVP).
I aim pretty much for most gear that has stam/agi/int on it. It is helpful that the extra stam on hunters won't keep them alive, but does let pets stay alive pretty long. The int is for longer times without viper and MM talent for INT-->AP.
I didn't have any problems in PVE except when a boss would ignore the pets (tanks) and go after a hunter. One that you had to heal through to win pretty much made me cry. Blizzard would think they would always have a healer in the group, so the boss putting a debuff on a player that does slow but long damage isn't so bad. But without a healer, I didn't have a way to deal with it. I gave up after potion, heal trinket, bandage, etc. and just sent in pets and LOS the boss and the pets killed the boss and the hunters just popped around corner and tagged (pets only doesn't count for kill) and mended. It took longer, but no one died.
For PVP, the normal people that screw with grouped up people hurt me. Bladestorming warrior, rogue (only kills 1, and he dies, but still hate it), shammy boxer (if they get in range), and disc priest (since, I can't do enough DPS to counter their fear, heal, penance, bubble, by that time, fear again). I use my pets as grenades and throw them at 70 yards. They really can kill people before they get to you. I usually just run away and let my pets chew on them, most people don't want to stop to kill a pet, so they just run at you and die.
My most success is in AV, I guard and back-cap stuff. Nothing like 5 pets, mean, mend pet rolling on them going after a player to make them poop their pants. Go ahead and DOT my pet, he has the health to live through it and his mend not only heals him, but takes your DOT off also. I can see you coming for about 60 yards away and with my tracker (SPY/Stalker), I don't even have to see (LOS) you to send my pets at you. Up a hill and feel safe, guess what, my pets can climb where I can't. Want to run away and feel like you have me vulnerable? It takes me .1 secs to get my pets back and they are full healed (nice trick, thanks Blizzard). Again, my vulnerability is when people ride up (fast mount) and AOE fear me or become unstoppable. If I was a HKer, I would be more mobile and that wouldn't be a problem, but I like to defend. It make me feel like I am helping instead of just HKing.