Please don't forget you must have really good drains for this extra water load. Have you considered a tankless water heater? Or at least a separate water heater for the master so that the rest if the household still has a hot water supply and pressure balance. That's something to consider also. I've often wondered, I must admit, how all of this is supposed to work with energy saving measures in place.

Change the pipes which material won't get rusty and corrosion, plastic or PVC is suitable. I think concealed rain shower system is more perfect for your bathroom. Check the link and choose the ideal set: http://www.homary.com/shower-faucets-shower-systems_c157

If the shower area is sufficiently big, I would prefer to opt for glass partition as that ensures that outside dry area does not get wet, which may happen in case of shower curtain. Having said that, I would opt for shower curtain if the shower area is small to avoid accidentally banging my elbow against the glass partition while taking shower and getting hurt.

Greetings From Dream Design, As per your Inputs we are suggestion you some idea -Floor drain should be near to shower and on the left side of it Pls share some images where your are planning for more understanding