I think the lack of fatigue is mostly due to low frequency rumble and vibration (I know, arguably the same thing) caused by the ICE. I'm not sure how much of a role stopping and charging plays. I drove straight home from the charger. In the Volt, I did the same drive but with a gas stop in the middle.
I really like how the car gives 3 values for range and shows a graphical bar that moves toward either extreme based on driving versus a single number that moves all over the place. It's much easier and quicker to judge any gains or loss in efficiency. As for the 60 to 65 difference, I thought it could be slope, but the timing was too convenient that range improved immediately after accelerating and stayed that way for the next 30-40 miles.
As for the regen paddle, I haven't noticed any time-dependency. It seems to engage the strongest regen available and hold it there. What might contribute to the time-dependent feel is the fact that a flat 70 kW of regen makes up more of the kinetic energy as you slow down, and thus causes harder deceleration as speed drops. Regen power actually decreases as speed decreases, but the strength gets stronger.
Holding the paddle and floating the throttle pedal will accomplish variable strength regen. In most situations, I think it's best for the paddle to immediately engage full-strength regen (yes, it eases into it over less than .5 seconds and doesn't slam you into the steering wheel
). There were several instances yesterday where I needed to slow down quickly and could do so without touching the brake pedal.
Yes, it has cruise control and I use it mostly on highways. Regardless of drive mode, cruise acts similar to L mode, where it will use as much regen as necessary to maintain speed (D mode is limited to 15 kW or so of regen unless you pull the paddle or push the brake pedal).