Since many long-haul airliners now have significant headroom for passenegers to walk about in, it occurred to me that this might be used to help fit more paying customers in -but also allow them a higher level of comfort.
In certain regions of the plane a double-deck seating arrangement could be built in. This would allow people to sit in a semi-reclining position, with significantly greater legroom, secure in the knowledge that no-one was about to crash the back of a seat into their lap.
These seats would also provide a more private space and incorporate a personal viewscreen on the rear of the seat above. There would be some adjustment in the height of the headrest to accommodate the taller-than average, but these seats would be the preferred option for more active travellers of average proportions.
In the event of an ’emergency’ the cellular construction of these seating spaces would provide people with a protective cocoon.