I forgot to say, Just make sure the pets can make up for what ur characters are missing. For example, if your water lacks speed- Id go with a Qlaya for seals/support. If that isn't the case for you, try to use the pets to fill in whats missing in ur team. If you dont use an earth most of the time, have one of your chars burst a xaolan! If you need more AoE- Fred, Clive, Roca, Hayate, and more!

Just make sure, You think of what you want from a pet. People have their own ideas, built your pets in a way to make up for what ur accounts are lacking as a party!