2 full floors or knee wall in a shed roof

We are currently planning the new construction of a single-family house. Shed roof with a 10° roof pitch, footprint of the house: 10.5 × 8.5 m. I am unsure about the roof: Either two full stories or knee wall with sloping roof in the upper floor. What would you prefer? (Info: two full stories would be permissible according to the plan).

Moin Moin

I would decide based on the use of the rooms with low ceiling height and the overall impression of the proportions.

Olli