My BST arsenal consists of the following:

12~36 Nursery Nazuna: TEs in Dynamis, Pulling, Aggro, High HP Tank, AoE Sleep.
12~24 Dipper Yuly: TH for farming, Eva Tank, Acc./Att. down, The go-to guy if i'm in t-r-o-u-b-l-e.
12 Gooey Gerard: Nice -pdt, Att./Def. down, slow on melee hits, nice addition.
>12 Other: These pets are made/bought on a "needs" basis.

Pet food:
12~24 Pet Food Eta
24~48 Pet Food Zeta
@/>12 Pet Food Epsilon
>99 Pet Poultice