Thanks everyone for all your feedback and tips. Below is the plan I have come up with. Not sure how clearly it will show up. Have wrestled with the position of the ovens and sink - thought about swapping them and about having them centred but then think there would be too far between fridge and cooktop/ovens. Cooktop is 600m gas, then two below bench 600mm electric ovens, 900mm rangehood. Sink is double drain, double sink (1550mm in all). I know this seems excessive and against trend but I could not live without my double drain as always defrosting meat, bottles of milk etc and like to have one clean side and one dirty side of the sink. I love the idea of a bi-fold door appliance cupboard for toaster, kettle, microwave but not sure how practical it really is. Will the doors when open be painful and stick out near the fridge???? Do like the idea of having all that stuff tucked away though. What do you think of dishwasher position? Think I will make that gap between island and bench with dishwasher 1300mm as suggested. The only drawers I'm planning on having are a bank of 3 x 3 800mm in the island. I know that are more economical space wise but trying to keep costs down. Should add that behind the L-shaped benches will be windows as much as possible. Looking forward to your feedback. Thanks greatly.

the house already has 4-5 bedrooms, 2 bathrooms and 4 living areas and already doesn't suit your family and that will only become more challenging as the kids grow older.. there's no space to add a double garage and mudroom, there's no where to expand the existing bedrooms and even if you moved the bedrooms upstairs there's still no where for the garage..hard to believe but you can easily spend your whole budget rearranging some rooms and updating the kitchen and bathrooms but you still wouldn't have the garage and bigger kids bedrooms unless they move into the other rooms or you build out the backyard and then how would you use the old bedrooms..much as i love a good reno i suggest that your budget would be better spent on a different house but some basic suggestions could include a rear extension (subject to the building ratios and correct setbacks) could be about 40sqm to add 2 bigger bedroooms, and a new laundry, use old laundry for more storage in bed 3 and a better bathroom, remove the wall between games room and old kitchen to create a more generous kitchen, dining and family room with better connection to outdoors, add a new ensuite and use old study as wiw, raise the floor in the old living room and add closeable doors for adult living and enclose the.entry porch and add a new entry to rumpus room for kids activities...based on very rough dimensions but could be something like this but assume at least double the budget and there's still no garage

Agree with @rojopen, creating such a large house on a massive block with the living areas facing south is not a great move. From a sustainability point of view, it’s madness. Please have a look at Lisa Booth and her instagram @bookenblend for ideas of large country houses. I see lots of workarounds, even if your view is south facing with pavilion style solutions and courtyards.

A good amount of adhd in our family so have a few ideas. Def a mudroom at the back door and a drop zone at the front door. De clutter absolutely everything- this is hard for ADHD, so you may need a secondary storage area in a shed where things are shifted to “just in case” and then disposed of a couple of times a year. Some separation of living spaces - all-in open plan isn’t relaxing at all. But my biggest piece of advice would be to analyse how you live and move through the spaces. What are you blockages that make things difficult? Do a walk through and note where the problems are. That will give you a priority list. But again de clutter - get less to manage and it will become easier. Arranging rooms and adding storage won’t help if you still have too much to manage. Unfortunately you can de clutter family members.