Designing Kitchens and Bathrooms - Options for Bathtub/Surround

I've really been enjoying this site since I discovered it and have gotten much helpful advice.

Here's my situation with my shower area. My home was built in the late 50's. I've got the original bathroom (Atleast I think it it) that is covered in pink tile on the floors and walls. Luckily the cast iron tub happens to be white. The Tub area has been leaking, I think the grout has worn out around the tiles that surround the tub and water has been seeping through and leaking in the basement. It's not a huge amount of water, just maybe a few drips each shower if any. But I want to get the problem fixed and get rid of the pink tiles.

Here are my options. I've got a window in the back of the shower so the tub surrounds probably won't work. A friend in the business recomended the Swanstone surrounds which is like a thin piece of marble. It can be cut around the window.

Another option is for me to retile the whole shower area. Which Im not opposed to either, I've tiled floors before but never walls in a bathroom. Would the tiles restick to the plaster walls? I know some water has probably penetrated the wall in parts and I'm sure the plaster is not in great shape. What would I replace the plaster with? Concrete Backer board?

The other thing I wanted done in this process is to get the drain, valve, and showerhead replaced with a more modern one. I will probably have a plumber do this part of the job because I dont want it to start leaking in the back after this project is done.

Or are there any other options I should look at? Should I keep the original White cast iron tub? I see no reason to get rid of it but if I'm getting knee deep in this project is there a reason I might want to replace it?

Any advice is greatly appreciated, BTW this is the only shower in my house so a timely project it not an option. Thanks again.

bump, Anyone?