another option is that you can send the pet on missions, since missions give the pet that goes exp (you can look here for some accumulated info on how much exp any given level of mission gives, although obviously you want to send a pet on missions it can do and work up from there as it levels)- could also be a handy way to keep the exp flow up if you have to leave to do something else for a while

(and if you get your reputation with esior's haven maxed, you can also buy equips from the esior's haven town hall; though lv0, these equips are about on-par with lv25 epic gear, stats-wise, which makes them very handy if you're leveling a new team up)

Yep, I just discovered missions give you exp after I sent my pets on missions to try and get some gold! :)

Thank you for the tip though and I had no idea about the good level 0 equipment so thank you!