Ive been researching for quite a while,,and Houzz photos have been a great resource.

This is very similar to our floor plan (yet to start building) ... same as you we have our backyard to the north, kitchen to the east, dining table in the middle, lounge to the west. And we had the exact same dilemma where to put the couches. We decided on position 1 but in an L shape with a couch along the west wall and north wall. And we will have two arm chairs or ottomans in your couch position 2. We decided on this because it feels more open and didn’t want the TV to be a main focal point. Don’t necessarily want to see the back of the couch either.

Congrats on the new home. Very exciting. As an experienced unpacker (we move every 2-3 years), the trick for organising is to stand in the space, consider how you will do things (ie imagine you’re cooking dinner, cleaning up, getting a drink etc) and, using sticky notes, decide where the easiest placement of kitchen utensils will be. You might, at this first stage, have six items that would be best in one cupboard. That’s normal. Choose the one(s) that you use most often, then with this in mind, redo the process. And be prepared to throw the whole system out after you’ve been in the house for a month or so Houses have a strange way of encouraging us to adapt to them no matter how intellectual/consistent/prepared we think we are

by "other options" i mean that you should consider all other options for locations of fixtures..there is already plumbing along each wall so swapping the location of shower and bath or vanity isn't as challenging as if there were no original plumbing in that area and if you plan to replace the fixtures and tiles rearranging the fixtures will only be a small percentage of the budget and it's a shame to limit the final result without at least considering other options..and although there is enough space to have the vanity hard up against the wall my suggestion is to have the vanity away from the wall to make it easier to clean and also because the small nook is an ideal space for hanging a hair dryer and with the luxury of so much space it will be easier to install a vanity away from the wall