You are off to a VERY good start, my dear! You have a lovely base color applied to them, now you just need to add some subtle highlights and shadows and that will elevate them even more!
The one with Usagi is especially my favorite. I love the way you colored her so soft and pale. It has such a delicate look. I think just slight shadows at the edges of her arms, collar bones and maybe around the chin would really capture it. ^^
Please do continue to show us more of your work!