Contemporary Gym Bathroom Design

Help with bathroom design in my basement.
We are using a contractor that specializes in basements, and prefers floors and walls to be water-resistant and mold-resistant.
1. They suggested we use their patented flooring where possible. https://www.basementsystems.com/basement-finishing/basement-flooring/thermaldry-floor-system.html
2. They suggested we use their patented walls as well. https://www.connecticutbasementsystems.com/basement-waterproofing/products/walls.html
3. We would like to use drop ceilings to access important pipes and valves in key areas (see provided floor plan) for those areas. While our contract suggested their ceiling, we are open to more aesthetic choices so long as they provide the required access.

Bathroom:
We would like glass separators to let natural light in from the south-facing windows. There is also a window on the west side for afternoon light.
We will have a tub (brand selected), sauna (brand & model selected) and shower in the bathroom, in addition to the vanity and toilet. The tub and sauna do not count towards the budget we listed.
We would also like a lounge area with seating and some storage.

Greenwich, CT, USA

Room & Board, Crate & Barrel, Restoration Hardware, Design within Reach, Wayfair, Jonathan Adler

As soon as possible