Sorry, our opinions differ here.
2m x 5.2m + gable full room height + sloping roof over the beds, I don’t consider that "impossible".
This has nothing to do with opinion: they are too narrow, too long in proportion. Your 2-meter line is an estimate, and your windows with a width of one meter probably couldn’t even have a lintel there.
Do your thing, but this dithering in the upper floor only leads to worsening improvements.
A rough redesign with a different building structure, namely somewhat deeper, can only bring advantages.
Sorry, but this cautious "it could be done better" doesn’t work anymore.
I’ve been saying it outright since 2019.
The approaches on the upper floor are okay, but if it doesn’t fit upstairs, then it doesn’t fit. You should have noticed that yourself when the utility room was still squeezed in up there.