Turning up fluid while turning down the air pressure is counterproductive to your desired result. Flow rate is a balance between air pressure and fluid volume and viscosity.
Not being there I would suggest that if you want more fluid and more atomization try increasing both the fluid rate and air pressure or just increase the air pressure. The fluid flow and amount of atomization is driven by the air pressure unless you change the viscosity of the fluid.
Regardless of what kind of equipment you are using you will get overspray, it's just minimized when you use an HVLP gun.
At least that's my take on it. Perhaps someone with more practical experience and less theory will chime in.
