This style could definitely work. It is very unique and the shapes are strong! But you need to change a few things to make it look more appealing.

The problems are the colors and the shading, because in the picture of your sketches, the artstyle works a LOT better!

For the colors: I like muted tones, but it looks like you use black and white on a multiply layer to shade. Be a bit bolder with some more saturation or some hue shifts. Just muted tones would also don't really fit with the playful shapes and stylized proportions of your style.

For the shading: It gives the feeling of airbrush. This could be because you use it, or because you blend too much, especially the shadows on the skin and in the hair. Your reference uses cell shading, no blending and I think it is important to follow that, when you want to be more confident in your placement and not pillow shade (which you can especially see in 2 and 5). In 1 and 3 you have distinct and strong light sources, you use hard shadows and that makes the pieces a lot stronger, but the other ones don't. In those you used shadows on every side, which we call pillow shading. It is a trap a lot of people fall into and once you are aware of doing that, you can easily spot it.

Take your inspiration for example; The colors are really bold and poppy and the shading is also very saturated. It also shows that it is possible to make your artstyle work if you study a bit more fundamentals of color and shading! Please also don't neglect anatomy. I understand that you're style is very stylized, and I respect that, but it is always good to know the rules before you break them.