Ahh yes hands my mortal foe. Trying to be more flowing and all.

I think the biggest thing in regards to proportions is making sure to measure and check how how big certain body parts in relation to one another. From the reference you gave we can see that you need shorten the width of the shoulders and stretch the neck and head vertically a bit more. Its a good first attempt though!

You've got a lot of good components in here but I think making sure they mesh well together should be a priority. For example I like your nose and the mouth you drew on their own. But when I look at them together, they don't look like they were drawn from the same reference in mind because of the angles.