It may not help with XP, but if still farming lucky yi or other fable pets, you can use the cheese strat,
Life Exchange. Cuts the fable pets HP in half, then you can use a regular pet with swarm to save time.
http://www.wowhead.com/petability=277 is found on 3 & 1/2 relatively easily obtainable pets, nether faerie dragon (wild) in feralas/dire maul, sprite darter hatchling (ah, mob drop in feralas) mini mindslayer (AQ25, or AH) ethereal soul trader (tcg, $250, or AH).
It makes most of the fabled pets manageable.
I'd probably go for the nether faerie as it takes ~10 mins to farm, and is half levelled for you. Mini mindslayer's easy to buy, or solo farm, but it's weak until it hits 15 and you can use the first tier 2 abilities. It looks better as well. Soul trader, if you can buy it, is formidable too. On my ah, it was 95k, so not really an option until the mystery box on the BMAH drops it.
All that said, if you still want to keep going with battle pet XP farming, get the list of flawless battle stone possible locations (the non-family ones are not BoA, and sell for 5k to 10k) , and park combat bot + PB + BPS in an area, it will swap in pets around the same level.
Hyjal starter area respawns are prolific, jade forest, deepholm, etc. pandaren areas become phased, so it can be good and/or bad to farm for pets in jade forest, krasarang, etc.