Right well, I was going to go for the orange background one (since I'm quite partial to orange) but someone had already critiqued that one and I figured you'd rather this on one that has none so far c:

So! I think most immediate two things for me in this are the colours and the fact that the paper has started to crinkle a little bit from too much moisture around the edges.

I'm not going to necessarily say that the crinkling is actually such a bad thing, although generally I would try to avoid it for the sake of not wanting to soak right through paper that can't absord that much moisture and causing rips/holes etc,. I actually find that since all the pieces in the series all have that effect, and because these are all presented digitally and are therefore flat, it is actually a kind of nice way of framing the piece. Not so sure about how much it physically moves in real life though, and like I said it can be best to try a range of papers in order to avoid anything too damaging.

The anatomy is for the most part good, it's a tricky kind of pose to begin with and at least in the sense of the arms and lower back, it seems to flow quite well. I think the most iffy thing about the pose is the angle of the chest appearing from behind the arm and the shoulder blade closest to the right side of the picture. That might be more due to shading than placement, in the case of the shoulder blade though, but I'm sure there are a few reference images of just this very pose that could help you to clear up things like that (won't be linking in this case since as you said these tips would need to apply to future pics).

Anyways, back to the colours, they are actually rather brilliant in my opinion (although I am heavily biased I suppose), I like that they actually do all work together rather well in fact, but my tolerance for bright colour seems to be a rare one. It's helped by the fact that the top an skirt have that darker material, accented with additional bright colours. It kind of grounds the character a bit that way. I especially love the way you blended the purple with the pink in the background.

I think the hair is done wonderfully, the flow is great and indicates a nice mix of realistic hair behaviour and cartoon style. Not to mention those colours used (and here I know I am most definitely biased!).

The face is something you can be proud of I think, as to replicate human faces is hard enough to achieve with striaght pencil drawing, but to bring it into a semi cartoon style and still have it remain recognisable is even harder. Based on seeing your ID pictures, I would say the thing you've tried to observe with the eyes and expression have really worked well (although a part of me wonders if maaaybe the head might seem a little too big in proportion to the body, but without actually seeing you standing in that way it's hard to know for sure if it's just my eyes or not).

Lastly, I want to say the folds in the fabric of the skirt are amazingly well done, perhaps there might be a way you could add a little more of that fine detail to the pink ribbon threading through the back of the top (perhaps the top you had in mind had thicker ribbon like that, but I feel like it would be nice if it were a little more delicate and thin as it would show a little more movement in the satin or whatever materials the ribbon is made of).

Anyways, I hope this is of some interest to you c: I'm not as experienced in traditional mediums as you are : P