If everyone can get their own personal instanced island (which is cool but nobody asked for it as far as I'm aware), then the devs most certainly could have introduced instanced houses.

I'm not sure why people feel that instanced houses would necessitate taking something away. They can leave the neighbourhoods as they are for the people that like them. It would just be nice to be offered a choice, especially now personal houses are limited to a small proportion of the wards.

The option of an instanced house would be a great addition to the game. There are not enough medium and large houses to meet demand. If they went for instanced then everyone could have the size they want, and probably have more items in the outside space.

The ward system is deeply flawed. Outside furnishing limits are tiny and there are a lot of unattractive plots. So many houses look straight into their neighbour's yard, some waterfront houses in Shirogane even face away from the water and the nice view across the bay. These issues are replicated across all the areas. There are a handful of really nice plots but far too many are badly positioned either with a poor view or well away from amenities. The only reason this isn't brought up more is because supply is so short; people are just grateful to get a house, any house.

I am not advocating that wards should be removed, but housing could be done much better. With instanced everyone could have a nice view and everyone could be close to the MB and the Bell. The ward system alone is never going to be able to meet demand on the busier worlds, an instanced system running alongside would be an elegant and practical solution to the shortage.