paint the end door a striking colour, horizontal stripes on the ceiling, and 3 large pendant lights. not sure how adventurous you are, but you could consider painting different colour "zones"- 3 different colurs as you walk down the passage.....possibly even 3 short carpet runners. i love the idea of wainscoting-but you will lose precious centimetres. You can get paintable wallpaper wainscotting.

Consider combining the concept of console with shoe storage. Check out this cabinet for example. http://www.mattblatt.com.au/Credenza-Storage/Bakbo-Tall-Cabinet.aspx?p19566c17#19568 It has a mid century modern feel and comes in both blond and walnut timber. While this style of cabinet is a bit taller than the average console or buffet it is still low enough for a mirror over the top. The advantage is it's a stylish piece of furniture that has shelves for shoes, hidden behind doors. Although the entry/hall is long it is already full of doors so try not to fill it up with furniture. A single cool looking piece of furniture on either walls #1 or #3 with some fabulous artwork on wall #5 and whichever of #1 and #3 doesn't have the cabinet on.

I understand the beam being installed when you did your earlier extension as that was an external wall, that's why I have suggested keeping part of the wall next to the island which was also an external wall, to support this, I will check this in the drawing to ensure it lines up for you. By opening up this wall as much as possible you are allowing more light back into the house The cost of running plumbing across I think is negative/comparable to moving the plumbing for the re positioned laundry and kitchen and removing any load bearing walls. Storage in the new kitchen is a big 2900 x 900 island of drawers for easy access, I have added a wall oven but that could become a 600 pantry with drawers in the lower part with a shelf above for small appliances. The wall with the TV could be a wall of narrow built in storage to be used in any way you need. This floor plan gives better flow between kitchen/family.dining/alfresco and better for unloading the car with the driveway running down beside the kitchen and verandah

my sister had to originally put her washer dryer at one end of the kitchen, european style. She actually found it way more convenient, and so when she got to upgrade and do over the kitchen, one end of the galley became the butlers pantry with washer and dryer in there as well. maybe it could work, but given all the advice above, I think avoiding moving walls is going to be important. Gosh, hopefully everyone's advice helps! Don't worry and take your time, I have been in my old house a year and I think i came up with 4 different floor plans before i realised what I needed to do. keep thinking it over and one day it will just hit you what needs to be done.