I've done the Madstad, have a Parabellum medium wind screen, and did the winglets. The other thing that helped was adding mirror extenders. I haven't done a comparison of all the changes and the incremental impact, but the mirror extenders were my last item and sealed the deal. Might be worth a shot - I think that for me, getting the mirrors a bit out of the windscreen turbelence helped avoid it being directed back to my helmet.
That said, I'm not a fluid dynamics engineer and really have no idea what is affecting what.
Eville Rich
2016 S10