ᐅ Planning the main underground utility line on a property with a slight slope

Hello, we are currently planning the main pipelines for our single-family house. Specifically, regarding the wastewater pipe and the drinking water supply on the property, we have received two different recommendations from our architect and the earthworks contractor about the pipeline routing. For the wastewater, our architect suggests the shortest route out of the foundation slab, which has the disadvantage of several 90° bends and a longer pipeline length. Our earthworks contractor recommends running the pipe under the foundation slab to avoid these bends and shorten the pipeline route; however, the downside is that it would be inaccessible if any issues arise.

Does anyone have a recommendation, or is there a third option that might be better?

The property has a slight slope towards the connection shafts (see elevation marks in the attached sketch).