Where are The Knights of Ren!!?

They would be nice, but they could really only work with SLKR. And he really doesn't need more lifters.

Make them like Inquisitors? Each has a leader for different scenarios perhaps, and some comps would be better for TW and some for GAC. But they also barely got screen time. Though again, Disguised Clone Trooper was cut, and characters like Pao, Bistan, and Eighth Brother didn’t get much screen time either. Who knows with CG, man

Dark Side Vision Rey isn't even canon, sooo...

I mean, she is. She's just less of a "character" and more a "possibility".

She is canon. She appears as a vision in Episode 9: Rise of Skywalker.

Barely canon then.

We can basically treat everything in the sequels as half-canon though assuming Ahsoka doesn’t die in season two of her show.  Knock on wood.

We better won't count sequels as canon.