A friend of mine provided an invaluable tip that I should’ve done earlier where you take a pet (preferably an aquatic pet like a Strand Crawler), level him to 25 and then power level your other pets using your main as a kind of invincible tank. The Strand Crawler in particular is quite strong in that the shield and heal-over-time ability allows it to survive quite well. The trick here with the Strand Crawler is to focus exclusively on non-flying pets while using the shield and heals to mitigate all damage. I would emphasize even more on locating a good rare (blue) one for really having a high amount of health.
To power level your pets, you pretty much need to have the Strand Crawler first at level 25 and part of your team. Whichever pet you want to level, you just make sure they can survive the first round. Then you switch to your Strand Crawler and destroy the enemy. Since your Strand Crawler should be level 25, the experience trickles down to the other pets that participate. This makes surviving the first round imperative since the pet that you’re trying to level just needs to make it out.
What I’ve been doing is farming in the Valley of the Four Winds using my Strand Crawler. This area is excellent as the pets are between levels 23-25, which will grant a considerable bonus experience to the lower level pets. I try to combine this activity with Lesser Charm Farming so that my toons that are low on Lesser Charms can receive some just so that they can receive their Mogu Runes for the week. Even if I lack the time to run everyone through the Throne of Thunder, I can at the very minimal accumulate enough charms for the bonus rolls when I am ready to run them through. Combine this with waiting in an LFR queue, and you have a fairly efficient and laid back method for progressing yourself.
Beyond preparing for LFR, my other goal in this activity is to ultimately build up a diverse team composed of each type of pet. Afterwards, I’ll circle back and do all the older trainers and pets to hopefully grab a few more rare pets from each zone. I’m avoiding anything that isn’t a rare for the most part. It really makes no sense to get anything of less than rare quality.
Going back to the Strand Crawler, if you’re looking for one, try hitting up the shore in Westfall. The coast in that region has quite a few of these types. So if you can snag a rare Strand Crawler, you’re pretty much set. You just need to get him to level 25 and you’ll be set.