Big NO to the sunken lounge. Just do higher ceilings for the whole ground floor.
These sunken rooms were popular in the US in the 1960-70, but are rarely seen these days, unless you are building on a hillside and need to change elevations due to the slope of the lot.
Most people don't want to be going up/down a few steps to move around a main floor.
The laundry seems a bit narrow. Do you plan on putting a washer and dryer in there?
I would also reconfigure the master closet, which just looks like a wide wasted hallway space.
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