Beyond a certain limit I don't really see what the point is... I remember BWee used to have these absolutely massive seats in their L1011's - but they were as hard as sitting on a pile of concrete blocks and the noise in the cabin also was a bit similar to being on a building site... oh yes and the cabin
'experience' was similar to being abused by a bunch of builders... Ahh them were the days... Lockheed L1011 - great cargo plane, sadly no use whatsoever for transporting humans...