I also give my children plenty of space, but 18 sqm children's rooms are already very, very large. And do you want to live alone on 230 sqm in 20 years? If you can easily handle a construction project of roundabout 1 million, then of course it is great to plan a lot of space. But I would really advise hiring a good architectural firm for that. Then even 230 sqm will be cozy, interesting, and usable with fewer people. More intelligent storage space, better utility rooms! - instead of a guest suite with its own bathroom. I see a lot of luxury there, but it is not luxuriously planned, just middle class simply in big. There are such fantastic architectural examples of luxurious family houses, I wouldn't just blow up a townhouse. I recently had the book 100 Dream Houses from Callwey Verlag placed on my desk. I can only recommend it as inspiration.