That should be practical now, even if it’s still not particularly generous.
Well, a combination of a 3-seater, 2-seater, and armchair certainly won’t fit there. You can also make the dining table smaller. And I don’t see the access to the balcony either.
However, I wonder under what conditions you are operating. It’s probably not about BT houses, where you only want to change the floor plans? And which target group do you want to address?
If I were single and looked at this apartment in reality, I would ask myself where there is space for a sofa.
I also don’t know if that’s allowed (doesn’t it have to be covered then? Like an attached stair housing??? Something like a corridor walk)
No, why? Here we have many attic conversions with attached stairs, certainly without a roof ;)