Sill height generally 1 meter, door threshold, building plan

If the construction plan includes the specifications you mentioned, then it makes little sense to discuss the validity of the plan. No one is forcing you to build there. Municipalities sometimes just have strange ideas about urban development.

... for development plans, one should also know the exact wording in order to interpret it

3.1.7
Knee wall (external wall height of an attic space between the top edge of the upper full floor ceiling and the lowered bottom point of the roof structure raised to enlarge the attic space)

The permissible knee wall height for gable roofs and offset shed roofs (one-sided) (note: other roof types are not allowed either) is uniformly 1.0 m.

Yes, it reads like that. Strange! There will be considerable differences in height. 2 full + roof including [Drempel] will also look strange in terms of proportions...