Are you thinking of contemporary or more traditional ? Here is an example with some 'spa' like qualities while still being relatively neutral.

I have a bathroom just like this and wondering the same question. I am thinking about removing the tub and just going with a shower? However not sure if that would be a "put off" for potential buyers in the future. I hope somebody helps answer our questions.

A "Neo-Angle" shower is a great solution for a small space. Here's a pic of one, Check out http://masqualityconstruction.com/2012/10/30/projects/ for more pics of this project.

Removing bath and only having a shower would not appeal to families with babies, so depends on what market you would be aiming at. However showers use much less water. How many bedrooms does the house have? Thinking of who might buy it.

If just a small area, think about 'glass splashbacks', sleek, modern and clean with no grouting! no-brainer!!