Floor plan optimization - approximately 160 sqm, 2 full floors, gable roof

There can never be too many or too large windows. :p

Yes, definitely :p But to each their own.

If I understand correctly, the niche is 203cm, plaster still needs to be applied, and then a 200cm bed won't fit anymore, right? Then you have to make sure the niche is at least 210cm, if you calculate 1.5cm of plaster per wall + paint etc. and a bit of clearance?

No, that might still not be enough. The mattress itself is usually 200 cm long, plus the bed frame. For such a niche, I would plan 220 cm if I were to make it.

For such a niche, I would plan 220 cm if I were to do it.

Me too. Just measure the bed lengths in the furniture store, not the mattresses ;) And you can leave out the baseboards ..

in the west you mean rather with parapet height

Not either, if you ask me. I have Terra doors on all three sides of the open space. But framing a sofa with a window is stupid. You need some protection behind you.

... and are you aware of the disadvantages you bring into the house with the many floor-to-ceiling windows on the south side, especially in midsummer? I rather don't think so.

In midsummer, you open the doors and only stay in the house to sleep anyway. The advantages during the much longer transitional period outweigh this. Yesterday morning, at 2 degrees outside temperature and sunshine, we were able to keep the large sliding door open. Simply brilliant. It was almost like having breakfast outside. In Germany, we have many more days when we are happy about the sun and long for warmth than days that are too hot. I would keep the originally planned windows in the living room, place the couch against the top wall of the plan, and put the TV in the corner between the windows. Then you can also enjoy the view outside wonderfully from the couch.

No, that might still not be enough in some cases. The mattress itself is usually 200 cm long, plus there is a bed frame. For such a niche, I would plan 220 cm if I were to make it.

But only if that is possible without problems in the floor plan. Otherwise, 2.10 m and buy box spring beds, which have no additional frames. These are the children's rooms, so there is no need for the possibility of maybe wanting to use slatted frames with motors or similar.

In the height of summer, you open the doors and still only stay in the house to sleep.
But the advantages during the much longer transitional periods outweigh this. Yesterday morning, with an outside temperature of 2 degrees and sunshine, we were able to leave the large sliding door open. Simply brilliant. It was almost like having breakfast outside.
After all, in Germany, there are many more days when you are happy about the sun and long for warmth than days that are too warm.

It looks somewhat similar for us; the days when one might feel it is too warm, which is always subjective, do not prevail in Germany. Great to take different perspectives into account for one’s considerations. Let’s see how we decide in the end.

We will leave the living room layout as it is for now. Without a corner glass area behind, one has the option to change it later if desired. Learned something new.

But only if this is unproblematic based on the floor plan. Otherwise, buy 2.10 m and box spring beds, which have no additional frames. These are the children's rooms, where you don't need the option to perhaps use motorized slatted frames or similar.

Let’s see what comes from the architect and how much can be adjusted here. For the bed, we also want to place frameless ones if possible, but someday the child will decide—no one knows that decision yet—so one has to train them to stick with frameless beds xD
Good that saw the measurements directly, so we can discuss it right away instead of only seeing it at the very end, if at all.