Do you have any other access to the backyard? Lane at the rear etc? If not... I like your plans but I wonder if you will miss the access down the driveway. Possibly a problem should you sell later on, or should you need to bring large amounts of materials etc into the rear yard. I'd think about using the front of the house for all the bedrooms. Possibly the sun starved middle room for the master suite. Extending it though to the room you have marked as pantry. I can't see the dimensions, so I hope it's big enough. And use all the rear space, minus the bump out, as living. You could maybe pull the kitchen into the centre, looking out to the yard, pantry + laundry behind it against the for mentioned bedroom. Splitting the living area up a little. And giving you much more living space.

"I didn't find that when we removed part of a rear wall wider than yours and then the sloping roof of metal or glass and large sliding doors will make great use of that wasted space and as mention much needed light back into the kitchen cheers" I didn't consider the sloped roof minimising structural impacts. I will get my builder to look into it as that will make use of that useless garden space, also integrating the outdoor living with indoors with nice stacker doors. The idea of moving WIR to bedroom 2 will surely make the Master an amazing room, however, I feel like we need to retain the upstairs retreat for energy savings. My thoughts are in the cold winter months, we spend time in the upstairs lounge (as heat rises) and in summer months, living rooms downstairs are used.

Think of recessing the Mirrored shaving cabinets as being recessed the same as the Niches in the shower wall, simply they remove/cut out the plaster board to the size/position and shape and frame that up with timber. The plaster board on the back of the recess belongs to the room behind and is the wall for that room, so makes no difference to your WIR. Just a thought if you go for the recessed wall cistern, when my brother inlaw did theirs the Architect suggested that they have a discreet panel screwed back over it, not fixed and plastered so that if any problems developed, Leaks etc it would be easy to access cheers

reluctant to lose the convenience of outside access to a toilet my suggestion sacrifices a little space off the lounge and bedroom to keep the extra toilet and use the original laundry space for a bigger ensuite with separate toilet and double vanities, the new extension makes a more spacious wiw with only standard doorway openings to the new rooms but the ideal outside door for the laundry will depend on the location of the drying area and you may decide that a western door or no outside door (and walk through the verandah?) could both add more counter space to the laundry and, much as i like the gable roof for the extension, it would be interesting to obtain a comparative quote for a simple skillion roof (and raked ceilings for the new laundry and wiw) that may save a lot of extra roof structure that doesn't add anything to the inside of the new rooms or streetscape and could be much cheaper..