I started off with 2 ravagers (DPS), 1 flyer (screech), 1 boar (charge), 1 wolf (furious howl). I LOVED it. No problems, too much fun and got up to 40's. But I want ferocity pets in WotLK, so I changed to 2 wolves (just left furious howl on auto, dont want to worry about it), 1 hyena (tendon rip-slowing), 1 flyer and 1 tallstrider (AOE 1 attack miss). It sucked leveling up the tallstrider, but other than that, they are 50's and I love it. No problems except in BRD room from hell until I figured out the timing. 2 parts I wish were different, imtimidation should not be tried to be applied if one is already on a mob (like slowing effects saying "A more powerful spell is already in use") and furious howl should give buffs numebers. It already has a little 1 in the corner, so it should just make the number 2. Not stack so you hit 10% harder, but so if one buff runs out, the next one can still go.
I really love pet classes, so I hope you have fun. Good luck.