May I ask your physical size? I'm 5' 10", 195 lbs, 32" inseam pant (31" reality). I'm also wearing the HJC modular helmet and using the stock screen set at the highest setting. While I'm not in a "cone of silence," I do not experience any buffeting. I get a lot more air than some other bikes I have owned, but it's a pretty clean flow. I do get a slight visual jitter in my prescription RayBans if I run highway speeds or higher with the HJC screen up, but with the helmet screen closed, my visual perception is smooth. In the closed position, the top helmet vents bring plenty of air, the chin vent never has airflow. There is wind noise, but nothing extraordinary. And, I've got my helmet hard-wired with computer speakers for wired sound so what wind noise I have is a moot point, as I'm almost always listening to music/GPS.
I'm interested in following your outcome because I may want less airflow during winter months. Right now I have no issues with the air volume I'm experiencing but I've only had the bike since mid-August.
If you're not living on the edge, you're taking up too much space.