I think many composite parts such as the fuselage don't scale down that well.
I meant purely for the additional strengthening for rear mount.
They find the risk of engine #1 taking out engine #2 too high. They want something inbetween..
The put something in between, its not impossible. Just don't use passengers as armour.
In reality, it's where 90% of the action is..
Maybe but LCC airlines tend to buy a single type and therefore it needs to cover all their needs and 700nm means that almost your entire market could be cannibalised by train travel.