After reviewing all your fantastic feedback, I've worked out what to do for colours (being me, however, I reserve the right to change my mind). I agree that it needs to be either the gold/orange or the grey, but when I put them all next to the background quilts it became obvious that I need to stick to softer subdued colours.
So I adjusted the grey head a little bit to be a bit more golden. This is the new version:
And this is the original grey:
And the original gold:
And by some miracle I already have fabric in that colour way! So I'll give it a go with a tiny trial version and move on to the panels if that goes ok.