Walk-in shower with wall, floor, or channel drain

With three planned bathrooms, the question currently arises as to how to drain the water from the three level-access showers. Wall drain, floor drain, or channel drain?

How have you solved this and where do you see the advantages and disadvantages?

Here is the basement bathroom:



Here is the ground floor bathroom:


And the attic (main) bathroom:

We had tiled showers with a drain channel. I didn't like that because the channel and the tile joints were difficult to clean. In the new bathrooms, we are therefore installing shower trays. They then have a "normal" drain. I think you have to pay attention to the drainage capacity.

The children each have a channel in their bathrooms, our bathroom has a discreet wall drain across the width of the walk-in shower. Cleaning is no problem.