Zone stretches across two slopes/soils

I have a couple zones that run along the perimeter of my yard. The beginning of the zone starts at a top of a hill with a fairly steep grade(i have a tool that can tell me slope %) and then finishes flattening out. This is a long run of approximately 150’.

My question is it better to set this zone for the bigger slope, or an average?

Also the zone stretches across two different soil types according to the soil survey site. The more steep zone is supposed to have available water of .18 and the flatter area is .17 does it really matter what setting i use?

As a further follow up my soil type is a slity clay loam. I am going to set the available water in the settings but which soil type should i choose?