I love window seats. They make you feel like you're in your own private world so you can really loose yourself in thought or a good book or indulge in a good cuddle with your cat or dog. I was tied between 2 and 4. I like a place where I can either stack pillows or lean back comfortably without leaning against the window and I definitely like the added perk of storage.

Very exciting to be building a new home! I would include a second sink with your layout. This will stop your guests coming into your pantry to fill up a glass or the kettle etc. particularly as you want to keep the mess hidden. I personally think it can be handy to have two sinks as this is often a pinch point with two cooks and with clean up vs prep for next course or coffee and tea after dinner. I think you are right about the window seat not being as desirable without the northern sun. Bedroom 1 or 5 could be a good option if you could imagine yourself sitting there with a good book. In terms of kitchen planning guides you can google "planning kitchen work zones" or similar. A couple of Houzz articles that are worth reading are: Kitchen Planning: Zoning Beyond the Basics https:/https://www.houzz.com.au/magazine/kitchen-planning-zoning-beyond-the-basics-stsetivw-vs~54574000 Forget Kitchen Triangles – Work Zones Are Where It's At https:/https://www.houzz.com.au/magazine/forget-kitchen-triangles-work-zones-are-where-its-at-stsetivw-vs~33838673 Good luck!

Is that a photoshopped pic of your place , or just a similar place ? There are too many styles trying to happen there IMO , not only the windows , and like oklouise says , somethings don't quite look right . I'd do bars ( frames ) about 200mm from the top of the two upstairs sets of windows , to match the downstairs style . Unlike ok lou , I don't like louvres -- they are drafty and don't really achieve much IMO -- a kid can put their hand and/or toys and/or your valuables out there , my personal preference is top-hinged with a folding stay at the sides , so they open 150-200mm but no further -- no-one can climb or fall in or out , can stay open overnight if warm , etc . I don't particularly like the upstairs balcony and gable , but I'm not keen on the entrance door treatment either , and without knowing what it looks like now , I may be tempted to replicate the 'double square' look of upstairs , downstairs too -- make it all the same theme . I'd keep the garage in the off-white , because if you look at the right side , both downstairs and upstairs look a bit boring IMO , with that flat dark finish -- the garage door done the same would add to the slab look . And while I'm being picky -- I personally think the black or extremely dark grey is too dark -- toned back just a bit would be better IMO -- you don't want it to look obviously grey , but a nice charcoal IMO . And finally -- the column bases look 'dirty' -- imagine how they would look in a gloss black tile on the top and also the 'skirtings' ( or a gloss black paint at a pinch ) ; with white gloss tiles where you have a light grey ( or , again , maybe the same paint as your other trim , but $5k of tiling would really add to those ) -- I think that would work with your black , or even a charcoal , 'main' colour . Anyway , just suggestions , and purely my viewpoint -- it's quite a nice but still simple design , just a couple of small things that would bug me if it was my place .

for the banquette to be wide enough to lay on it would need to be at least as deep as a narrow single bed which makes it too wide to sit on comfortably without a very thick back rest or a giant pile of cushions to clutter up the space...why not consider a back and sideless freestanding daybed so the primary purpose is laying down and the sitting to dine is only short term and doesn't need a backrest ....this example or similar with taller legs would be a simple economical way to add the day bed feeling without expensive built ins and two along the window wall could look quite inviting with a simple throw and scatter cushion