Hey Fluxgate, I think the image conveys what you described. I like the simple style. It looks a bit like a 2D sidescroller game. Anyways, here are my thoughts on how to improve what you mentioned:
The style you are going for is a quite simple one, based on simple shapes, flat colors / gradients and hard edges. So I think part of what makes the character look like shes floating is the soft gray shadow behind her. The shadow right now is "added" to the ground, but actually it should be the opposite. So a lightsource only lightens up the areas it hits, and usually never darkens them. In order for there to be a dark shadow, you probably would need to change the lighting in the picture a bit. It's quite hard to explain, so I did an overpainting. I hope you dont mind.
Basically I darkened the image to get darker values overall, then considered where the light would hit and added the shadow of the character. As you can see the shadow that is cast by the light source does not get darker than the rest of the image.
Other than that as said I really like the idea and style of your image. : )
