This feels like it has the Kaheera, the Orphanguard problem: Once you built a deck w/o no artifacts, you kinda have no reason not to run this companion.

Companion abilities somewhat need to be something that's harder to happen by accident.

On another note: The cheapest creatures that tap for two mana without a restriction how to use it are Fyndhorn Elder, Palladium Myr, Gyre Engineer etc.

Seeing this at mana value 2 even without companion is a big power boost.

I was only thinking about commander, where you have to give up sol ring at minimum. That's a big cost