Some of your colours are barely noticeable (like the two purples on the scarf, which read as a single colour unless you zoom in and look closely). I also feel like the red outlines are unnecessary and distracting (since they're lighter than the objects they enclose). Have you trid having no outlines at all? With this sort of simple style, it could work pretty well.
If you're interested in getting feedback on your work to help you learn faster, I recommend checking out the PJ forum. There's a WIP section where you're more likely to get feedback, and you could have some back-and-forth going on there where you can make corrections to your work, whereas with the main gallery you basically get one chance to have your work seen.
Thanks for your tip! I'll try doing so and I'll look more into the forums! Thanks!