P.s. Technology should be reachable via the shortest route from the connection point (street). Whether the development is permitted is stated in the building regulations of your federal state.
The good thing is - there is a lot of room to shorten the floor plan... I'm also not a fan of mini children's rooms - but 28 sqm is huge and I would find anything up to 12 sqm okay...
The design should pretty much achieve spot-on practical room sizes when scaled to the budget ;-)
First of all, I want to praise you for drawing your house with simple but effective means like digital programs with pencil and graph paper. You get a much better feel for the house and the plot because you simply get more sense for the measurements.
I can only agree with this praise, as well as the diagnosis:
If you look at the upper floor, you have drawn the ground floor so that your wishes work quite generously and without bottlenecks, and the upper floor emerged from that.
Compare this with "The upper floor takes priority" on "Bauen jetzt," where I explained the more clever design sequence.
First of all, it needs to be clarified what should be included in the 550k. Depending on that, the number of square meters must be reduced and then the floor plan should be looked at again. You have already received suggestions for that.