I wonder about the engine braking capabilities of the 3-cylinder engine. It is really weak on our F20 116i, and the new engine is supposed to have even lower friction. Even more energy will be wasted by heat in the brakes. I can't even feel the contribution from the electric energy regeneration.
I would also have liked to have units on the time axis of the step response graph, and an old fashioned N/A-engine like the M42B18 for reference. The throttle response has become very sluggish over the years, compared to what it used to be like.
(An electric hybrid motor in the drive line could perhaps deal with both issues)
Other than that, the concept looks good.