Perhaps the kitchen is your bete noir? If it is you can do a lot with some new blinds and lampshades. Try some potted plants on the window ledge this can brighten most kitchens. If the paint-work really is past its prime then you need to decide whether you need a whole new paint job or whether you can get away with touching up the doors and base boards. If your bedroom needs a face-lift then try some new bed covers and toning curtains. Add a few cushions to your bed and you immediately have a more luxurious look.
Floating shelves look fragile to the naked eye because of the way they sit on the wall. All the workings of the brackets are hidden so it seems as though they are floating there on the wall. In reality they are usually much stronger than other types of shelves which are supported with traditional brackets and screws.