Idea: Extending House Feature

[Edax]

Some of the cottages like the Shirogane Castle clearly have a 2nd floor, even if the inside does not. I see no reason why small plots cannot be upgraded to be taller, inside and outside.
Okay sure, this might result in everyone's view getting constricted, but in super-populated servers like the one I'm in, all the plots are already taken. In the real world, we'd start building upwards like it's New York. And some functional upper floor balconies would be great at still providing a view. It would be even better if we can rent out a floor to other players for a weekly/monthly income.