I live in a house with the same dimensions and a slightly different floor plan downstairs: the WC and HT have moved to the middle of the hallway. HT is opposite the stairs, WC under the stairs. This gives more width in the hallway and a narrower connecting piece in the open space. I don't have a plan on hand right now, but somewhere here in the forum there is a thread about it.
In our case, the architect planned the kitchen in the narrow connecting piece. I have the pantry and office there and pushed the kitchen to the back into the large room with the terrace.
I think you have quite a lot of open space for dining + living.
From experience, I can say that the hallway with a cloakroom is really important. I have a narrow shoe cabinet and a bicycle in the hallway and you can still walk through. I hang jackets on an old-school coat stand.
I find living in such a house really practical. Not too much area to clean but everything is practical and easy to use. Of course, a little more house width would be nicer, but it’s really quite okay. The hallway could be a bit brighter. I have a door with lots of glass and a frosted glass film as the front door. That brings in some light but not that much.
link to my floor plan, very similar house to yours: