Here is my lovely first floor lobby bathroom!
I aimed at making this plumbing system as compact as possible so that it does not intrude with the space nor the underground soil as much as possible. I found plumbing surprisingly quick and easy relative to having to deal with the nightmare that was HVAC! Furthermore, I realized that I sacrificed in my design here a bit because my ADA considerations were overlooked at the raw SF of the bathroom space. I was only able to fit 3 toilets and 3 urinals for the Mens and just 5 toilets in the Womens room respectively. For a space that will invite nearly 200-300 people in a given day, that is a very small size bathroom.
If I were to do it differently, I'd make sure to oversize my bathroom first then decrease it as need be.
Additionally, my zoning area does not permit a greywater collection system as the city or Sammamish largely controls the sanitary reservoir on their own. I had to keep this in mind and omitted the grey water system entirely.