I am 6' tall, 32" inseam, 220 lbs, multiple jackets but none as smooth as yours, seat in the low position, windshield in the low position with the top mount spaced 1/4" forward, OEM Wind Deflectors. I get some head body movement though during windy and/or traffic conditions.
The wind deflectors can cause the Tenere to move around a bit though they push the wind from coming into and on the rider. If it wasn't for cold and rain I would probably not have them.
I came from the KLR and I used to suggest to others to remove items to see if they were the cause for buffeting. Two suggestions: 1. Space the top of the windshield forward to see if this makes a difference. 2. Remove the windshield to see what the difference is. Another test: Ride behind a big rig, bobtail, bus, etc to see what effect that creates. Then ride into clean air to see the difference.