The house I am imagining wouldn’t have a basement but it might need to have a deep foundation so may as well put a utility crawlway there. But it would have a small wine cellar, so I would have the access to the utility crawlway behind a sliding wine rack and wood panel.
For me it would have to be a really big house. With the relatives mentioned by the OP, that would mean 45 people. It would be 50 if those in committed relationships add their SO. I can think of 3 of these people I really do not want to socialize with so the answer would be no, I would not do this.