One thing I would've liked to know was how a random cat ended up as the first guardian of alpha earth.

It’s not a Random Cat? It’s GCAT. He’s the Ectobiological clone of Jaspers mixed with Jake’s BARK Code to give him First Guardian Powers, just like Bec is Halley’s Ecto clone mixed with Rose’s MEOW Code. We actually even see Crockertier Jane bringing Jake’s notebook to the Ectomachine in the Temple to create him. This is one of the reasons, too, why I believe Condy sabotaged the First Guardian- There’s Lil Cal and a Cue Ball in the Session, in this Universe, LE’s Seed and Vessel are within, and yet Lord Scratch is not the First Guardian? And she sent the Brains of the Operation to do something as simple as pressing a button? I like headcanoning that Condy used Jane to alter the locked coordinates of the Ecto-machine that’d be otherwise targeting the Cue Ball and Lil Cal, and set them just on Jaspers, making a First Guardian she could easily control with the Taurus Animal Communion.