There are tons of papers available that would go with your midcentury home. Many people tire of a paper quicker than they are ready to redecorate and they can also look dated in a couple of years. Metallic papers were big im midcentury...perhaps a metallic silver paper? Are you also considering paint? You can get it in so many textures and a blue wall to match the blue in your loveseat would be lovely with some midcentury art and sculpture, or photographs on it. A mirrored wall with or without art or sculpture would also work with midcentury. These treatments are easier to adapt should you wish to change the look slightly from time to time. I would suggest replacing your stairrail with chrome or acrylic if that is in the budget...see how well the loveseat frame looks with the fabric? I hope you will post the "after" photos for us to see. Above all, enjoy the process!

I never love open shelving in a modern kitchen they are dust and grease traps but I would hang horizontal glass front cabinets and paint that wall some awesome color ,run your backsplash up to bottom of window all across. If you have space make the island top larger and paint out the other wall of cabinets to match main ones. The island top could be something much different than the others

The fence will end up being a modern picket fence, We aren't sure if we should grass the two squares or plant it out, it's a nice sunny spot, but we have nosey neighbours that we are trying to make disappear, if then it becomes more private then a seated area could be really nice, Hopefully the right plants will work or we will have to go with plan B, of installing barbed wire and two wild Dobermans!

This made me laugh: http://www.theguardian.com/environment/2016/jun/09/seagull-turns-orange-after-falling-into-vat-of-chicken-tikka-masala I couldn't copy the picture, but it's hilarious.