A simple trick I learnt : How to find the exact complementary colour. Get the colour in a strong light.,,,sunlight preferable. Isolate it and stare at it intently for a minute or so, Close both eyes and see if you can see a colour..."reflected" on the inside of your eyelids.....THAT is the colour that will be a good complement for the one you want . In this instance, since the colour is mixed...you might "see" several. Looking at this electronic colour...( not the ideal scenario)...but.what I see is a light greeny/ grey, a swatch of the colour would be easier to do this with. Put the swatch on a white background and....stare,,,,so..."light grey" is close but maybe with a touch of green. Hope it is successful.

I agree paint may be more versatile - but the right wallpaper on a feature wall with that deer head would be so freaking awesome ! Depending on your colour scheme, if you go with a vintage or art deco pattern, fairly subtle and with a slight texture in it, that'll beautifully offset the deer. And if it's the right choice then you won't want to change it for the next few years anyway. So definitely wallpaper - there's some great 'wall candy' around :-) Good Luck !

If you are keeping the rug, take the blue or pink out of it, and use that as paint colour. Only problem is I think the rug may be too small. We like to consider each room as a whole, can you post different views please? Leave out things you're not keeping in there.

Looks good. Before I read through discussion, I had these thoughts. You could look at painting on the front of the wall only, not in the porch/entranceway area underneath, double strength of main colour. So you could as an option get a test pot of Dulux double Self Destruct or even triple. I would not use Monument, or similar to the roof color as it will disappear into the roof. I also think the front fence would look better painted a stronger colour from your existing but as it seems it has just been painted perhaps you could do that, when and if you liked, to cut down expense. On the Dulux website they also give you colours that look good with Self Destruct. (Picture below). Another option is look towards going bold like a strong blue or blue green. Something like in the picture. That's my feature wall, Resene Billabong. ...or a dirty purple or a blood red. It's starting to get really personal of what your tastes are. Perhaps you could Half or Quarter the main house colour in the entranceway so it still flows but gives you more light. Exciting stuff!