is the TV room to be included in the master suite, what are the measurements of the rooms and where is the third dormer??

where is north and do you have gorgeous views out those big windows and where does the bedroom door open to? ...there isn't a much better layout although moving the wall will allow more wall space in the wiw and a more generous ensuite with careful choice of fixtures including a 90cm wide vanity with drop in basin, narrow toilet in a 80cm wide space and walk in shower 160cm x 90cm and wide mirror doored wall cabinet and a ventilating sklight the ensuite should be much more comfortable and allows extra wall space for 4.65m of storage in the wiw plus dressing space and room for 3 x 90cm wide chests of drawers and a chair etc

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..

I also like oklouise plan. good insulation is the key. In your original posted plan, Maybe change where the beds are positioned in the room. I think there is some bad feng shui if your head is backing onto a toilet. Apart from the noise factor, every time the toilet is flushed.