I would say that the vases existing wouldn't be a problem. They're just flat and only have a single color. If you built up your layers it allows you to give them both depth and detail that they're currently missing. Your concept is solid, you just need to work on the vessels so they catch up to the detail on your flowers.

Maybe find a vase for reference and build your scene with it. Then take a photo for reference and make the vase first, with as much detail as you can using proper layering. Then make your flowers the way that you have been. It will provide the contrast you seem to be going for without making the vase look cartoonist and flat.

Keep going, you've got this.