Thank you all.
That olive green suggestion @minesagin37 might be the solution to it all, actually, i’ll think about that when I see the results of my planned test...
So I am going to investigate the blue option a bit further as my preference given the business of the room generally is to have the sofas tone in rather than contrast, here’s my plan:
Samples of Hague Blue and Stiffkey Blue, painted up on A3 sheets.
Dye some stuff Dylon Denim Blue -old pillow cases, touch up an old pair of jeans and a clipping of my sofa fabric -it came with a sample, presumably for repairs. Do similar with Navy Blue -I could do with a couple of Navy pillowcases for my bedroom. I’ll then work out what two blues go well together/ I can live with.
The long term plan is new sofa but after a whole load of renovations paid for this year, I could do with 12 months to save again. So any compromises will be made on the sofa colour rather than the walls. We are far north and I think Stiffkey might be too cold.
The sofas are two small John Lewis Bailey sofas with entirely removable cotton covers. They are over 10 years old and been washed many, many times so I think they should dye well despite having had flame retardant coating originally. They are currently duck egg blue (with a black biro smiley face on one arm) with matching stitching which I know is unlikely to take up any dye. It’s going to take about 14 dylon pods and a whole lot of washing machine time but i’ve weighed the covers and think (hope) it is do-able. Although at the age of the sofas, which have supported my enormous arse through 3 pregnancies and prolonged time in one spot breast feeding, if it goes wrong then so be it!