I would add some more doors downstairs as shown attached,
Study and WIP for noise control, The pantry door so you can use blender without disturbing rest of house.
Hall opposite bathroom for privacy of guest staying in bedroom.

Thanks Kate .. any other key factors to consider when designing ??

You still do not have a separate powder room upstairs for use by people using the cinema room. Take the toilet out of the bathroom, and create a separate powder room.

That plan looks distinctively familiar, have you posted it before?

Yes an earlier version - my query isn’t more about feedback on the plan and more about main considerations while designing a house

• layoout being one of it - but also ventilation or heating /cooling - what else ??

Did I miss the north direction arrow?

Also more doors. Doors from garage and cloakroom not shown. Add door swinging into cloakroom towards powder room from garage and a slider to hall
And storage for pool and gardening equipment and bicycles. Need to plan for these as you don’t want you view to pool spoiled...

@brizcs - east is the main entrance - Pool is on the west - North is side of courtyard and family

I would be turning things around a bit. In Melbourne, you want to maximise the sun in winter, which means living rooms should face north and have large windows. Morning sun is often appreciated in bedrooms, so consider facing them east - never west as they get hot afternoon sun. Studies and living areas used in the late afternoon/evening should never face west either as they will be very hot in summer. I would definitely relocated the cinema room and family room windows to face north, not west, and Bed 1 windows to face south rather than west (though a smaller frosted glass door or a well shaded door out to the pool area might be a good idea.) You will need some very good shading over the dining room windows to keep out the hot summer afternoon sun. I agree upstairs needs a separate cloak room.

I agree re upstairs powder room but wonder where you are going to store all the occasional use things - suitcases, Xmas decorations, camping gear, tools, etc etc. It is a huge house with many rooms but it really needs to work... You will end up with 4 or 5 toilets... Do you need that many or can you create multi-way bathroom to allow toilet separate from bathing? Why don't you have door direct into pantry from garage for ease of bringing groceries in? More rooms does not necessarily mean more usability.

Definitely should have a door from pantry to garage.

What about taking the upstairs toilet out of the bathroom and putting it into a separate cloak room with small vanity instead of adding yet another toilet?

I also don't like the zigzag path through the WIR from the Master Bedroom to the ensuite. I would find that annoying.