This thread deals with almost exactly the questions you’re asking:
https://www.warcraftpets.com/community/forum/viewtopic.php?f=3&t=16783
so do please read it!
There is no best trio. There is no team that will defeat all battles. You choose different pets for different battles.
In that thread above, I said:
For a beginner’s first team:
I’d go with Anubisath Idol, no question. Complete no-brainer.
My second pick would be Chrominius.
These first two pets are tanky all-rounders you can rely on to hammer at any opponent.
- My third would be a really tough choice between Teroclaw Hatchling, Iron Starlette, and Mechanical Pandaren Dragonling.
That third slot is more interesting. They’re all first-rate pets in their different fields. For a more experienced battler, I’d rank the Teroclaw higher; the other two are more straightforward to use.
A critical factor would be the rarity of Mechanical Pandaren Dragonling. You want a Blue MPD.
I’ve actually been working on a suggested list of early pets to aim for as a new battler. It’s NOT finished, but here are the current priority sections as I have them at the moment:
Priority 1
Anubisath Idol
Chrominius
Clockwork Gnome
Darkmoon Zeppelin
Emerald Proto-Whelp P/P
Emperor Crab P/P
Ikky
Iron Starlette H/H, P/P, P/S
Mechanical Pandaren Dragonling
Nexus Whelpling P/P
Rabbit / Spring Rabbit / any 357-speed rabbit S/S
Unborn Val’kyr
Zandalari Anklerender / Kneebiter / Footslasher P/P, S/S, P/B
Priority 2
Darkmoon Tonk
Fel Flame H/H, H/S
Feline Familiar
Gilnean Raven/Crow
Grumpy
Hyjal Wisp
Infected Squirrel H/P
Kun-Lai Runt P/P, P/B
Leopard Tree Frog S/S
Mechanical Axebeak P/P, H/P
Mudshell Conch / Shimmershell Snail H/P
Nether Faerie Dragon S/S
Scourged Whelpling H/H
Stitched Pup
Teroclaw Hatchling
Yellow Moth P/P
This thread has a longer list of suggestions and opinions.
https://www.warcraftpets.com/community/forum/viewtopic.php?f=3&t=16391