This might be a crazy idea, but what if the curse was something that you could cast after your commander leaves the field, rather than being able to recast your commander. Flavor wise I kind of just like the idea of, your commander stays dead but they leave the field with a curse. And, I guess in part I am also pitching this because it may help with some random commander/curse combo that could end up being too strong. Oathbreaker had problems with that where there just were commander/spell combos that ended up making the format not much fun because people weren't playing their decks, they were playing their command zone.

Seems like it could be fun : )

FormOverFunction (best Treebeard voice) A wizard should know better : )

I'd say maybe using etb creatures and Ashnod's Altar to sac them, get mana to pay into making tokens, get etbs on tokens. All of the incarnations would work great (though maybe kind of salt inducing) to evoke Fury ping mana dorks, sac to ashnod's, gain mana to gain a token. I don't think Ashnod's Altar will go infinite or anything, but could be a good value engine.

Also, just random cards

Clarion Spirit if you are using etbs and casting creatures will just randomly get you value and spirits

Kabira Takedown  ^Flip because you might have lots of creatures and if not it's just a land

Curiosity effects like, Reconnaissance Mission and Thopter Spy Network and Grazilaxx, Illithid Scholar

Also, any token deck loves Cultural Exchange as a finisher : ) Get your etbs and value cheap and then trade a whole bunch of 1/1s for an opponents best board.

And way off topic, but I feel like Zinnia should be a plant or tree folk, because for real : )

I mean, if anything Nissa should have been a squirrel because they literally plant seeds.

But yeah, I think either of your choices, raven or black cat, totally make way more sense.

I do think that most if not all of them kinda don't make a lot of sense. Jace and/or Tamiyo should have at least been some kind of sea creature. An octopus or cuddlefish maybe.