Hi yoscholtz. I can see you have a definitely understanding of what you like, and perhaps only struggle in putting what's in your mind together in your space. Try a few things by moving things around or layering grouped objects you like, then edit the room by taking things away until you are happy. It costs nothing to play with your interior, you often surprise yourself by following someone else's idea, only because they see your space very different to the person living in it. So.. From your layout I suggest the following. Push back the sofa at least to the first pane of glass, so it defines a bigger living zone, as these leather sofas are very heavy looking. Place a neutral area rug big enough to go under the foot of each sofa, making he space feel generous and inviting. Turn your coffee able to face the same direction as your tv, place a floor lamp in your corner next to the tv, or my preference is to add a table lamp to the tv low line. A pair of framed prints in your style above the sofa on the wall, and in the dining room, a mirror on the wall to reflect the living area, bringing the house together. don't overload your cushions, either place them all at one end of each sofa, one with a throw (the wall sofa) and stack some complimentary cushions on this end. This allows youth introduce colour. Don't just choose blue, bring in another tone, whether it be close or complimentary, blended colour is softer, and feels more personal, unlike display lounges. To make it feel lived in, allow for personal accents, framed pictures do it a little, it more so your accents and objects you place usually come from a theme or share something in common. And so these areas don't feel disconnected to each other, borrow something from each space and take it into the next joining space, for example, a colour, a texture or object. I've seen turquoise ceramic side tables like drums that Are perforated metal, or geometric ceramic ones that would look great in your lounge corner, or a round ottoman. The more soft fabric you bring in, the more it will feel inviting.

Option 1 is fine but you have no vanity space and these tend to look poky in smaller bathrooms. This is a smaller bathroom, this can be eliminated with say frosted glass walls. But you are changing a bathroom for one that is similar sized, worst case mirror the WC over so it gets some ventilation. Option 2 are you kidding me a full length window in the shower? where is the entry to the master? is it coming off the living room? Option 2 good use of the hall, but the planning of a free standing bath in this small main bathroom will make it appeal smaller is there no shower in this option? If you are going to the expense of making wall changes, what about taking the bath out to the eaves, if you have them which will give you 600 mm more space? If the master is coming off the living room? If the overall internal dimension is 4.2 M and you need say 900 mm for entry to ensuite and 100 mm walls, that leaves you with 3.2 M for ensuite. Looks like you are taking out lots of walls, so to me if you changed the access to the WIR and ensuite to the other side, the vanity can be near the full length window, which solves the water issues of it being in a shower, and it would be nice to be pushed out the 600 mm like the bathroom, and if you were willing to give up say 300 mm of space from the bedroom side, 4.2 x 3.1 than you could have hanging space (which goes into that proposed new access point), on two sides and then a total wall of storage in shelves or drawers or places to put shoes and bags and ties and smalls on the ensuite side.

I'd agree with adding darker colours to the mix... if reupholstering things is not in the budget just by adding chocolate, charcoal or navy blue to the chair and bedding will help. Add some rougher textures, chunky knits, pin stripes, vintage linen and right on trend velvet.... Adairs have a sale for another couple of days on their linen and other products https://www.adairs.com.au/search/?q=Vintage+washed+linen Accessories to consider are things made of dark marble, timbers, geometric shapes and gold... A bold feature wall could give some mood to the room again in the above colours.

You could consider custom joinery that actually looks freestanding - purposefully creating a gap from the edge of the fireplace surround to the wardrobe & on the wall side also. This would also mean that it really does not matter if the front of the cupboards do not align with the front of the fireplace. Adding a nicely detailed leg, and a feature handle (you can get some really unique Australian made ones these days) to give some visual interest to the otherwise minimal finishes. Keep it simple & classic so it ages with your child's taste and preferences. As an example, The Design Files recent article has an image of a cupboard in a lounge area, that could be adapted to two double door units on either side of the fireplace https://thedesignfiles.net/2019/10/interiors-house-p-cjh-studio/. Seems perfect for a child of any age, or even if you want to convert the room to a more 'grown up purpose' once they leave home ;-)