Beautiful home! Any pic that comes up when you Google "rustic bathrooms".

Lauren Liess' Master Bath

For me it would depend what the bathroom had a view of. I’d want it to try to bring the outside in so you could continue to relax-in-nature (usually one of the reasons people have lake houses) while inside. So something that brought in trees and wood textures if it faced the woods, and something that felt like an extension of the lake (blues?) if it faced that way.

I don’t like bathrooms to be too rustic because rustic makes me think of splinters, which is not an enjoyable thought in a space you’re supposed to be less-clothed in.

I would like something like these from Houzz pages:

https://www.houzz.com/photos/bathroom-traditional-bathroom-st-louis-phvw-vp~1569498

https://www.houzz.com/photos/edgemont-road-house-montclair-nj-traditional-bathroom-new-york-phvw-vp~2610733

https://www.houzz.com/photos/kids-bathroom-beach-style-bathroom-minneapolis-phvw-vp~90921177

A functional one that does not takes hours to clean since I would like to be at the lake. I do not believe it would have to be rustic but maybe slate floors.