Your ideas and suggestions / improvements to our semi-detached house

Yep, basement!
I have an 8x10 semi-detached house. There is already enough space in the entrance area. The shower fits easily into the guest bathroom. The hallway is big enough to handle two-way traffic.
How many people are/want to be? If no children are coming, then the technology room is in the upper floor. With children, better a basement or the technology room in an extension behind/in the garage?
Instead of a mini pantry, better one more kitchen cabinet, saving a wall. We integrated the wardrobe into the stairwell.

@ypg:10.7m :) The party wall has no external insulation

Let yourself be inspired by standard floor plans of semi-detached houses and terraced houses, as mentioned above: technology on the upper floor or attic, or positioned entirely at the front, smaller hallway, smaller staircase, smaller rooms! You will be building a semi-detached house and not a villa - that's just how it is ;)