it's not shaded, even tho you're using four different colors for both pallets (which is probably too many at this scale). shading would help a TON to in this, giving it a lot more depth, helping tell the hair from the arms etc.
actually, for your colors, even zooming in, I barely notice the contrast between a lot of them. at this scale, probably two reds and two greys, collapsing to a same purply color, would be all you need. that brings me to the color scheme, actually: there's not a connection between the red and grey, so I'd recommend adding a bit of red to your metal, it might make it fit more, giving a lot of unity to the piece.
finally, I'm confused on what this is: with the lack of contrast/shading, all i see is like a head and eye and chains, everything else is really indistinguishable. the line art also contributes to this, its really sloppy on the arms.
my biggest recommendation: don't "crank things out" when you're trying to learn. focus on making one piece the very best it can be, instead of doing as many as possible. you'll learn a lot better that way, that's how I learned. and I think with a better single piece, you'll learn techniques which will help all your pieces look a lot better, more developed, and more "mature."
to be blunt, and sorry if it's rude: right now the witch / fox / this thing all seem unfinished to me, but you've just moved past em. you say you're happy with em, I understand, but you could do a lot better (heck, I could too!)