HI Renae, I like your colour choice black & white, I went all white in my renovations of kitchen & bathroom and just by adding a bright coloured fruit bowl, vase, pot plant and a small painting in the kitchen made the kitchen look fresh whilst in the bathroom I just added bright towels bath mat. I changed the colours in winter to warm colours and cooler colours in the summer both kitchen and bathroom. These are simple and cheap things to change a look whilst if you go for timber it can date quickly and timber absorbs moisture so it has to be looked after (time consuming and $) looking forward to seeing your finished renovations.

my concern with the windows was to make sure that there is a window for light and ventilation for each separate space but it should be quite simple to build shelves to suit the windows in the wiw but what is the size of the windows in each room? that is width, height and distance above the floor?

I hope you don't mind... seeing the external pics I have a totally different idea! But don't worry I don't expect you to actually use it, and it's just a rough sketch. You don't need to extend the footprint at all in my opinion. based on the picture of the front of house your drawing is a bit out... the entry stair actually sits to the left of the front door I think. so there is a little more room there, but i'm not sure if its wide enough. So maybe there is enough room to put a hallway back in and create a master suite upstairs? The front deck becomes a private retreat and I put the bath out there! It's only accessible from the master and bed 4. If you don't need that many bedrooms maybe even leave the master and bed 4 combined and have a huuuuge master area. there's still the study downstairs that could also be a spare bedroom. I thought as the front deck is so private it could be really luxurious. The old kitchen becomes the walk-through robe and ensuite. The new kitchen goes straight under the old, and the kitchenette becomes the bathroom,accessible from the pool. the downstairs kitchen is connected to the dining and living, but the posts define the areas. The kitchen can have a halfwall with a servery-style opening between the posts, and will still have that connection. I didn't draw it in on the downstairs picture, but the entry needs to be pushed a little forward and then the stairs run up from the left corner and arrive where the original entry was upstairs. The downstairs living is accessed straight from the entry at front and opens onto the front patio, under the back deck becomes the back patio. I feel like you have less new to build and retain more of the original layout. in fact the upstairs bathroom is entirely intact.

the distance between the shower and vanity in the family bathroom is too cramped...my suggestions include a 1700 x 750 back to wall corner bath, 1200 x 450 vanity and a bigger shower with half wall for toilet roll holder and moving the bathroom door shortens the hall and allows wall space for towel rails and moving the ensuite door makes the toilet more private