Is there a way to design/create a shower that is less prone to mold?
General construction advice for 'general' showers:

In/on the walls:


use RedGard as a vapor barrier over the cement board
use paperless or blueboard sheetrock
use mildew resistant pain
adequately vent the room with a proper exhaust fan


In the shower construction itself:


seal all caulk properly
make sure standing water can't puddle


Now, all that said, I pretty much agree. Showers as they are today aren't really designed as well as they should be IMHO. 

For inexpensive solutions, I'm actually a fan of the more modern pre-moulded systems. You can get systems that look quite nice for under $1500 that come in 3 or 4 full-wall sections with gasket seems. I know folks tend to consider them 'cheaper' than a true tiled shower, but I actually find them much more intriguing from an engineering standpoint. They just make more sense to me in a modern home.

For more quirky/unique solutions, I've seen:


metal sheeting. Corrugated Galvanized sheets, for example. Copper as another.
all glass
sealed monolithic concrete (note that concrete is extremely porous so would have to be sealed with something like an epoxy coating)


And...most recently...we stayed at a new hotel a few weeks ago where the shower walls were made out of solid slabs of the same counter-top material as the vanity. It looked really nice actually, I'm guessing it was a Corian like product.