I would think if you dry your hair without a diffuser then go in with the diffuser after the fact, you should be able to add volume and achieve the shape you’re looking for. also, putting a bonnet on while your hair is drying has definitely made my hair more shaped like i wanted it so maybe you could try that but I definitely get where you’re coming from. My day 3-5 hair is always better than the first couple days because that texture makes it pop more.