Yes, the name "Dragon’s Den" probably doesn’t come from nowhere.
First of all: I like the "townhouse" with its three full floors. An architectural style that is increasingly found again in big cities, especially due to the small footprint. Because of my profession, I get to visit such new buildings quite often and have grown fond of them. Personally, I also like the exterior view, but that is always very individual. My mother-in-law covered her hallway with a white, somewhat subtle but still glittery wallpaper – it scares me. For her, for example, my bathroom is too dark. So what. You have to like the exterior view.
The only thing to consider is whether the upper floor will actually be used in old age, despite stair lifts etc. In general, after the children have moved out, you have a lot of space that must also be maintained/cleaned and is probably used less. But again: Usually you don’t design your house to be senior-friendly or make the children’s rooms particularly small just to have less effort at 65+. With your budget, you could surely afford a cleaning lady, or you sell, etc. A granny flat is always a tricky thing, many plan it but only a few actually implement it in the end, because you don’t want someone looking down into the garden from above, or the loud stomping overhead is more annoying than expected. And once the house is paid off, you usually don’t rely on the income anyway. Privacy is more important than rental income. So if you like the attic and can and want to afford it with all financial consequences, then go ahead and enjoy it.
But now to the floor plan: I want to point out that this is my taste and my idea/experience. It may not apply to you:
1. Kitchen: I am not a fan of U-shaped kitchens, especially not with a kitchen island. That’s too many walking routes for me. I like it when I have everything more or less within one step and one hand movement. With a smaller U-shape, that applies again, but it no longer looks as nice then. A kitchen island, nicely large, possibly even wider than usual, parallel to the "main kitchen" I like visually and functionally more. A well thought-out classic. I might even swap kitchen and living room.
2. As already mentioned: No TV downstairs could become a problem. But it doesn’t have to. Since you’re planning a connection there anyway, for me that’s no further point of discussion.
3. I’m just too dumb to recognize this right now. Ground floor and first floor 2.75 m clear height? If so, I find that good, otherwise it would at least feel oppressive on the ground floor.
4. The wardrobe and entrance area is nice. It is spacious and cleverly designed, so that there is a lot of storage space with little floor space consumption.
5. What I would personally change immediately, but maybe does not fit you currently because the children are still small, is to give the children their own level and the parents their own level as well. There should still be room for a home office in the 2nd floor, also on the 1st floor, but then it would be right next to the children’s rooms. When the children are older, I would find it great if they and the parents each have more privacy and might not have to be particularly quiet because mom and dad are sleeping next door. And the upper floor would be perfect for a wellness oasis with a view (depending on how the adjacent development turns out). Such a thing can’t be realized in a normal "standard" single-family house. I admit, that would be a little dream of mine.
6. I do not find the bathroom bad at first glance. But it will certainly also evoke ambivalent feelings here. The dimensions would be interesting for better evaluation.
Best regards from the North.