I like your plan but I don't think a pattern on the bed wall is a good idea. The carpet already has a lot of pattern so I'd keep that wall a solid, dark color, from the rug. Add some sparkle like mercury lamps for the bedside tables for interest.

What is the rest of the house like? Would you like overflow sleeping areas or more storage? If you can't raise the floor (and the ceiling?) you might consider building in some comfortable seating/storage areas that use pillows/cushions and play up the multi-level idea and make it look intentional. Similar in concept to the stepped couch.

Hi Helen. I thought I might share photos of my kitchen- which happens to be on a farm- as the layout is very similar to yours. We planned to do white subway tiles (and still might as we are just doing the bathrooms with the tiles and will see what we have left...) but used clear coated cement board as a temporary measure and find it quite serviceable as we haven't finished the kitchen. We did the open shelves first and then added bits and pieces of shelving afterwards. These are white washed Douglas Fir. The shelves just below the temporary ply bench top (going to do polished concrete benchtops later) are lined with galvanised tin. The lazy Susan in the corner cupboards are really handy! Hope these photos might be of interest. It's a very serviceable kitchen work in progress!

You could install racking for both sides of the room, toys & clothes that aren't being used can go into large plastic containers with lids. The two bikes could be hung from the wall or ceiling. And yes, anything that doesn't need to be there, move it on. There are so many hooks and storage options available that it would be very easy to sort this out and by getting a lot of it off the floor.