Living on different levels is exciting and spends a high living comfort.
In particular, split-level houses are ideal for building on a slope as the levels fit to the natural ground. The way of building in split-levels has many advantages, not only for grounds on a slope but also on plain plots:
By the way of building with cubes, it spends privacy and hidden places. It spends relatively more internal space and less corridor and staircase space. It is a flexible way of building as if required we may add levels or build it with less. Last but not least half basements are more efficient than full basements.