What I would really like is to get (mod I guess) a neutral/clutch/freewheel momentary button.
I haven checked the efficiency of adaptive regen yet, and don't bother changing from the default Normal mode + Level 3 regen.
I like heavy regen without going to one pedal (as I charge my SR to 100%) but it always bother me that the car doesn't coast at all and it is pretty much impossible for me to keep at 0% power use.
So lately when I got up a mountain and back, when the road is not too windy (more than 5 seconds between turns I would say) I have been using the ger select knob to "declutch" putting the car in neutral to accelerate and use the Drive Level 3 regen to decelerate before turns.
On a 14km trip with the way up being +566m and -125m, I don't even look at the efficiency as it is well past 23kWh/100km. Plus starting at 100% mind you, so a big part of the down slope are with practically no regen.
But on the return trip, I can go in the negative until the last 2 km.
The difficulty to go in the negative on slow trips (even more at night) is the baseline power usage is significant so you need to still be fast enough to not have that baseload eat up all the regen you do on the bends. With a momentary button to free wheel instead of using the knob, I'm sure I would feel comfortable using on more twisty roads as I wouldn't need to leave myself a margin to fumble and still have time brake and waste the energy as the knob is not the most reliable control for a moving car.
Here is a picture taken right after the 5.7km 287m down stretch of road where I can unclutch and go in the negative (before that the constant acceleration and regen is good but stays positive), before the last 2.2km after which the last 2 pictures are taken :
A speed limiter mode for the governor would also work well, speed limiter + no auto regen would probably works well too, but the regen and brakes are well blended so to never waste energy one would need to ride the brake pedal carefully enough to not engage it.
Having and driving an electric car makes me think that economy measurement should not be output based but input based. What good does it do if drivers waste the efficiency of a car that could be efficient ? I would love it if on Eco mode my car could remove all the guesswork and skill to squeeze all the efficiency out of it. It might just drive the innovation toward the improving the speed governor/limiter side from the "how to optimize and screw with that particular test" side.