I have been chasing this issue for a while now - here are some observations from my experience (ymmv)
I did a fly in drive out when I bought my latest bike. I was unprepared, in that I didnt really take the several hundred mile two day trip home that serious - just like another sunday ride. So a couple of LONG days with lots of wind noise (no ear plugs). I did learn that if I crunched my shoulders up and pinched off the flow around the base of my helmet, it helped a lot. (note I have an Arai helmet). But much too much road noise, and much more than I ever remember from my '00 that I had for a few years (but Im old now, and have little kids, so dont remember all that well anymore..... but I digress)
So I tried a vario touring screen. It has a small secondary screen at the top lip that can be adjusted to change the slipstream height. It seemed to help a 'little'. Very small improvement, so off with that.
Then I took the screen off entirely for a bit. BIG IMPROVEMENT! So decided that I liked the smooth air better than the buffeting where the two screens I had tried seemed to hit me for my size and riding position (note that I DO believe your individual size, riding position, helmet, and clothing ALL have an impact).
So I just cut about 3 inches off the stock screen and I like it much better now.
Also, I got one of the windjammer skirts. As mentioned, wind coming around the base of the helmet is a big contributor. Closing this off with the windjammer DID help. Yes it makes fogging more frequent, and also is harder to get the helmet on/off. But it helps so Im using it (I should note that wind noise is my #1 detractor from enjoyment when riding the VFR)
Google 'helmet skirt' and you will see there are products out there that the racing guys use all the time - I bet they work well.
Also note that I believe my leather riding jacket is not the greatest, and I can create a minor effect by how its fastened around the collar and top buttons. But its not an option for me not to wear it, so until I go with something different its what I have.
Finally - I ALWAYS WEAR EAR PLIGS. The soft foamies. But I will switch to some ear plugs for music at some point, and do like the looks of those custom complete ear designs.
Hearing is a lifetime! Loss is irreversible (I have severe hearing loss in one ear already and want to protect what I have left). If you ride without hearing protection you WILL suffer hearing loss (just my opinion)
In summary:
+1 on the wind jammer
+1 on a helmet that gives you low wind noise (varies by individual)
+1 on cutting the screen back and riding in the clean airstream
+10 on ear plugs
:)