In my house, our stairs are carpeted and the upstairs/downstairs levels are floating floorboards. The stairs worked out too expensive to do so we changed carpet colour to compliment the colour of the timber. It looks fine :) I think they're separate levels and you won't see them together so should look good either way!

The photo below is my suggestion for colour of floor. Furniture should be darker - similar to below. For the rug - choose one colour from the artwork and find a similar coloured rug. Don't put a mantle over the fireplace - it could be a health hazard - bumps and bruises. Blinds - unless you want them to make a statement I think white - to match window frames would be fine.

This must be close to the 100th time you've asked a similar question. And you've spoken to Dulux already.Tell us what you don't like about the colours suggested so far, that will give us an idea of what you're after.

I agree that it can be upsetting at this stage but your timber will all darken naturally and the difference will become less obvious over time and once you have furniture and rugs in place it's likely to be one of those issues that only you and no one else will notice. And I defy anyone to not have something like this in their house which has been newly built/renovated. I know this isn't terribly helpful but I don't think ripping anything up to start again or going to great lengths to seek recompense from supplier/installer is going to help your blood pressure either (by all means raise concerns with them and ask for suggestions from them).