I'm torn between 2, 3 and 4 but I'll have to go with the printed Grassington sofa as It's so unique!

Lounge doorway is 81cm wide with door on, and would be 82cm if could take off. Very old fittings that seem to have been painted over many times so getting door off may be an issue. Doorway height is 196cm Hallway width is 77.5cm and height wise no issue in hall - very high ceilings. The hallway width is probably the biggest problem. The only access to lounge is through this hallway door, and the width is only 77.5cm. The Next team were trying to twist it around but the sofa was just too big. They actually ended up accidentally putting a hole in my wall trying to do it!

I think you could go various ways. I like the rug, can it go under the sofa feet? (Hard to tell how wide it is from the photo). The art seems a bit small, it often works better if it's hung just a few inches over the sofa to connect with it. I'm not sure if this art is big enough though as 4 seater sofa sizes vary. I'd probably repeat the brass for a coffee table or floor lamp and then I've picked up colours in the art for cushions but maybe vary the texture with linen etc rather than just all velvet. I think it will look great once furnished and accessorised 😊

Have a look on YouTube, there are some great tutorials about adding stuffing to the cushions to pep them up. There are also companies who make replacement foam infills for sofas either online, or contact local upholsterers, if they are open.