Welcome to the burrow~
As Stormy and LM said, you can determine what mob you may want to join heavily depends on your meerkat's personality.
For example, if she's kind and gentle, she can be in the Tiny Kats, the Comets, the Willows, the Zippers, the Oreos or the Jumaa. Or if she's vicious, then the Midnights, Reapers, or the Phantoms would be perfect for that kind of personality.
We also have two newer mobs we moved over from Stormy's site, they're called the Skittles and the Fireballs, which I don't know too much about sadly. XD Ask Stormy if you wanna know more. ^^
But I hope you stay an active member and I look forward to roleplaying with you~