Planning our single-family house - What do you think about the design?

Nothing prevents us from turning the staircase 90 degrees at the top.
As a layman, it is always difficult to plan something like this because I never knew how long or wide a staircase would be.
We liked a floor plan of a prefabricated house and then tried to redesign it and adapt it to our plot.
I don't like staircases turned 180°C and none that start with a turn at the bottom like in old buildings.
For these reasons, because I had such a staircase before, we wanted a different staircase in our house and that’s when we fell in love with a straight staircase.
In this regard, it was fixed and I planned the floor plan around the staircase by cutting out all the furniture to scale and constantly moving everything back and forth until everything was to our satisfaction.
Then I gave this floor plan to our architect and he drew everything else.
Since we already have a 117 sqm apartment, we planned everything so that we hardly have to buy any new furniture except for some things in the kitchen and the 2 children's rooms need to be furnished; the rest is sufficiently available and only 2 years old.

But, honestly, a large living room, a huge couch, and then with your back to the window ... that's not ideal. And the path to the kitchen always passing by the living area, that's not great either. You sit there in the evening, eventually you have teenage kids who want to quickly grab a drink in the kitchen with friends or even cook together with friends or something like that.

And, as I said, the entrance to Child 2 is a pure compromise. The stairs... well. Kids also tend to grow taller than their parents, and you can see from the drawing that running down a curved staircase is at least cramped for people over 180 cm.

Just let go of that and free yourselves. Can the couch be arranged flexibly? Or your wall unit?

The couch but not the [WZ Möbel] consists of a display cabinet, TV cabinet, and highboard

You can do it, everything is allowed.... But it is unusual to line up the display cabinet and the like like that next to each other. The display cabinet is needed in the dining area and the highboard somewhere in between. If you are convinced of the implementation of the house plan, then that's okay. However, I am surprised, since the proposals are not significantly different, but in small details more practical, that you defend the mistakes and also do not let them stand. What was your original question again?

In the dining area, we have an old buffet cabinet and an old solid table, no more space available for anything else. Then I tried to fit everything in with the other plan from kbt09. TV wall approx. 170, so two parts side by side are not possible, which I would then have to place somewhere else in the living-dining area where there is no space for it. So it simply doesn't fit downstairs, and we find the bathroom layout from the kbt09 plan terrible. Please don't take it badly, it's just our opinion, I am very grateful to you for all other comments.