I happen to like a really good quaity shower pan in acrylic as for the walls I like acrylic there too but tiles are also nice . If you go tiles I like the bathroom floor and shower walls the same 12 x24 tile in porcelain in a color that is neutral. If you keep the finishes simple and plain it allows you to paint a different color or do different accessories and that is easy to change/

Thank you for your suggestions. What do you think of a solid surface shower pan? I also have planned to bathe my very large dog in the walk-in shower and didn't want a shower pan that could scratch easily from dog nails. Regarding the shower walls, what are your thoughts on porcelain slabs instead of porcelain tiles to eliminate grout lines?

There are so nice shower pans with a bit of texture that should work for the dog yes of course you can do panels other than acrylic and they also have the benfit of fewer grout lines they are usually expensive compared to the acrylic but for sure a nice choice .I have a great pyrenese there is no wayIever attempt to bath him in the house he weighs 148 Lbs 20 lbs more than me so jave not had this issue.