I recently switched to a modular helmet. That solve the itching problem on most of the lower face issues.
Most of last season I wore a half shell, I hade very few issues with bugs and rocks getting in my face. Having a somewhat larger windshield helps a lot with that.
Not sure about the being able to hear more around me thing with a half shell helmet. Me personally, I can hear more with the full face/modular helmets as I have less wind noise directly in my ears. I guess that just another example of personal preference and what works for one doesn't necessarily work for another.
......I'd rather wake up in the middle of nowhere then in any city on earth.
*2014 VN900 Custom (16,200 miles and counting)