So, I'm going to list out the ones I don't feel are quite ready to be placeholders yet, since most of your work is good enough:
Malduval
Brontogon (very debatable, since I don't know how to improve it)
Serberine (for now, I think it'd be confused with Chiarame. Which isn't too far off but the problem is there)
Caribrisk (also debatable, but I'd like to take a better look at Stantler first before making any judgment)
Leoracle
Vilephist (Not entirely sure on this, but there's something about how the head fits together that's bothering me)
And add to the list:
Illumbra
Atlaxa
Cackinge

Everything else is fine in a placeholder capacity or better. Unicrown is perhaps the benchmark for one that wouldn't be accepted apart from a placeholder, mainly due to the fact that it appears fairly small and weak and not looking at the opponent.