Is fine plaster (Q2 lime cement or gypsum) sufficient for living space?

Addition: the rework by my husband took several hours. Certainly 20+ hrs.

The secret is: Consciously incorporate the unevenness into the design. My tip: Apply [Sto Sil Struktur medium innen] with a brush or roller plus touch-up with a ceiling brush.

We have moved significantly from Q2 to Q3 + non-woven fabric or non-woven wallpaper. Only one utility room remained in Q2, and I am very glad that we don’t have that throughout the entire house. The total additional cost is 11,000 EUR for 285 sqm of living space. (Wandflächen weiß ich nicht)

We painted Q2 directly in the basement and Q3 + fleece in the house, and the differences are more than obvious. I also wouldn't know how to incorporate that into a design. For a loft charm, you need significantly coarser textures again.

... Take the unevenness consciously as a design feature. My tip: Sto Sil Struktur medium ...

... Q2 ... For a loft charm, much coarser structures are needed again.

Thank you very much for the hints! We are currently also about to do or have done the interior walls (sand-lime brick masonry + sprayed lime-cement plaster Q2) and interior exterior walls (smooth precast concrete elements, as well as ceiling) of our newly built waterproof basement. For the lime-cement plaster walls, we have a surcharge offer from the painting company of about 26 euros/sqm wall (including surcharges for silicate paint and Q3 filling with fleece insert and mineral material), which might be a bit too elaborate for basement rooms.
For the planned better basement rooms ("hobby/guest"), however, the applied lime-cement plaster does not yet seem smooth enough to achieve a nice look with just paint or fleece wallpaper.
On the other hand, as mentioned above, the walls are already too smooth for an effective coarse look (and since we are designing not an Eppendorf loft but a Hamburg suburb basement, it should also be rather homey and cozy ...)

We will follow up on the tip about StoSil Struktur Medium. Sto states in the technical data sheet: "For plastered surfaces, the spackling quality level Q3 - Q4 is required." This presumably refers to result requirements in normal living rooms, and perhaps we will try it first in the house connection-/utility room or storage room to see how it turns out.

We can live well with Sto Sil in Q2. Really, even our visitor doesn’t notice it negatively. As I said, we didn't simply roll it on, but my brother went ahead with the fur roller and applied the stuff heavily. I followed behind with a ceiling brush and wiped in large semicircles. Since there are grains in the stuff, it now intentionally looks uneven. My brother says architects love that, they like to specify it, and the painter then charges an astronomical price for work that any journeyman with an apprentice as help can do. Try it in the basement, and I tell you, it will make its way upstairs.