Here is what I use for the celestial pets if that helps, its fairly generic with plenty of different pets to fit the bill for most.
Yu'la: Clock'em with Jab and Dodge can generally solo her, and its an easy pet to get (just need rank 4 in brawlers guild). Dodge the lift-offs, rest of the time spam jab.
Chi-Chi: Any snails can pretty easily kill him, just keep shell shield up, refreshing it on the turns he does his dodge thing, rest of the time spam ooze touch. High power snails are best. Note you need at least two snails, three is safest.
Zao: Any two pets with explode and any one pet with ion cannon beats him every time. doesn't really even matter what pets they are. What I normally use is netherspace abyssal, mininfernal, and menagerie custodian, but really any pets that have those abilities work. I start with abyssal, meteor strike, immolate, explode, then bring in mininfernal, explode immediately, then bring in custodian and ion cannon immediately and Zao is dead.
Xu-Fu: This is the only one where I have specific set-up, but it works very consistently. It includes lesser voidcaller (any breed, the higher power the better though), Lil' Bad Wolf (s/s breed), and Nether Faerie Dragon (s/s breed, sprite darter hatchling works also and is always s/s breed). The fight goes every time like this.
Start with Voidcaller
Round 1: Curse of Doom
Round 2: Illusionary Barrier
Round 3: Switch to Wolf
Round 4: Pass while Xu-fu breaks the barrier
Round 5: Howl
Round 6: Dodge
Round 7: Claw
Round 8: Claw
(wolf dies, bring in faerie dragon)
Round 9: Arcane Blast
Round 10: Evanescence
Round 11: Arcane Blast
Round 12: Arcane Blast
The standard val'kyr, water spirit, anything with howl setup works just fine on Xu-fu also (curse of doom, unholy ascension, geyser, whirlpool, howl), but I have always felt that tactic was almost like cheating which is why I always look for alternate ways to handle fights.