Thanks for keeping feedback coming! It is much appreciated.
I think pets being more suited towards taking damage rather than dealing damage goes a little deeper than "high attack or high defense". Being vastly better at absorbing damage than dealing damage is pretty universal across all jug pets.
Pets are huge, meaty bags of HP with a -87.5% Damage Taken cap. Every single jug pet has these properties, even if some have more HP than others. Some have strong elemental resistances in addition to this. I don't think anyone could ever complain about the ability of even the flimsiest jug pet to take damage.
Looking at the offense of all jug pets, they have their auto-attack function and their auto-attacks and the ability to auto-attack. The best Ready command for damage is currently Nursery Nuzuna's "Rage", because it affects the sheep's auto-attacks. All direct-damage Ready commands are currently on par with two auto-attack rounds at best.
The damage from these auto-attacks is very good against lower level and lower defense stuff, but falls off of a cliff against anything with decent defense and about a half-dozen levels above the pet. Being that there is no command to cram a Red Curry bun down a normally herbivorous sheep's throat or hurl a whole Marinara Pizza +1 between a ladybug's mandibles in hopes of finding a mouth of sorts, there's not much a player can do to soften this massive drop.
If Beastmaster pets are meant to be brick walls of HP that can deal some damage to some enemies, then mission accomplished and full-speed ahead. If Beastmaster pets are meant to be balanced between offense and defense, then something is not working out.