I think you should know quite precisely what technical equipment is going into this room. A large one can be too small and a small one too big. Once you know the devices, this can be clarified quite easily. I like the design by but also basically find your last one here interesting as well. The question is whether you wouldn’t have to bend the entire design again when sanding the mentioned edges. I also see the washer/dryer rather opposite the entrance in the corner; moreover, it needs to be clarified where the drain would come out at the bottom. On the ground floor, I see slightly shifted walls anyway, which might be load-bearing walls and therefore cannot be moved arbitrarily.
The very first and thus most important decision would be the placement of the house. Now you have a so-called north-facing plot and somehow I have the impression that you are not so happy with it. It’s like on a tour bus where all 50 guests want to sit in the front row and fear other seats would be inherently bad; but that’s not the case! I like the idea that came up here to move the house all the way forward because at the back you have the field, so peace and privacy. If the house stands far forward, a second (wooden) terrace could be reachable over a jetty or a nice path at the rear end of the property, as you often see in Sweden, for example. Although we have pretty much a south side here, we still built such a second terrace from which you can nicely look at the house. But we sit 95% of the time under the terrace roof, so in the shade. Our neighbors with north- and northeast-facing terraces also have their covered terrace at the back and don’t find that bad. Now in winter you miss the sun, but by May/June at the latest you often flee from it, get blinded by it, and look for shade.
If it were summer now, I would recommend you go and see it there in person and spend a longer time for a picnic to really get your own feeling for it. You can write, read or measure a lot but in the end your own perception decides what you find pleasant. If it is possible to raise the house 2-3 steps then you won’t have to dig away too much at the back. If you then sit a little away from the house, you have the sun again and also your south side.