To me, this sounds like another marketing Best Show from sram. The right words would be “a drive train that may survive power shifts” …
They’d better develop integrated eletronics with the motor manufacturers to allow the sistem to manage power delivery during shifting.
Something like the...
I am happy with a 40t as lowest cog, the smaller, the lighter and cheaper, the better.
Now, I can't imagine why the distance to the ground should be significant? if it ever hits the ground, I would rather bail out and be far from the bike when this happens :)
The chain should be properly sized...
As per battery drain, I believe that what di2 drains, along a ride, would not move an ebike more than a few yards... I could keep shifting for hours after the motor power is dead, so this is not a problem.
Imagine a drivetrain that manages power cutting while shifting. That is an unbeatable...
I am using a shimano di2 xt 11s on my sepctralon 2018, it was an easy plug and play job and has been working flawlessly for almost 2 years. It seems to me that shimano integration between motor and the new generation di2 will become the best solution for ebike drivetrain in a short time.