Interesting write up. I do have the rev hang issue although you learn to live with it. Can't complain about fumes despite a fair number of the 2,500 miles covered so far being with the roof off.
Buffeting is not an issue providing side screens are used, indeed at anything above country lane speeds I find it uncomfortable without them.
Like yourself I've found after market front shocks, AVO in my case, afford a more controlled front end. The damping on the coil sprung rear on mine seems very firm so will leave that alone. Steering is light with good turn in, aided by Wolf rebound spring bearings.
As with my M3W I often drive on the tacho on motorways although once you allow for parallax the speedo is surprisingly accurate. Sixth gear is very high (35mph/1000rpm) so despite all that power you really need to change down to overtake swiftly on motorways. Fourth will give you 133 mph! and in fifth you will have hit the published top speed well before the rev limit is hit.
Finally note the average mpg readout is geared to US gallons. When converted I'm getting 31 mpg at the moment.
Hope you continue to enjoy yours as much as I do
