Agree completely, a lot of sofas have a seat length that's far too long. They look nice but with your feet down the back of the sofa is so far away you need to stack four or five cushions together to get any contact!When I bought mine I sat on them all in the shop.
Far too many are very deep front to beck. Most were so bad that if my knees were bent on the front edge, my bum was too far back from the rear upright cushion resulting in a nasty slouch.
I rejected all those, and got one that fitted me (guests don't have to live with it, I do!)