UPDATE: BMW Cancels Range-Extender Option For i3 In Europe
Presumably, bigger battery + shorter Euro driving ranges = no need for REx. U.S. still gets it. It'll be interesting to see if the bigger battery in the 2019s alters the mix of i3/i3 REx I see, as that usually runs about 3:1 in favor of the REx. EPA range of the new 42.2 kWh battery is expected to be around 150-155 miles.
Guy [I have lots of experience designing/selling off-grid AE systems, some using EVs but don't own one. Local trips are by foot, bike and/or rapid transit].
The 'best' is the enemy of 'good enough'. Copper shot, not Silver bullets.