Bathroom fixtures command a large part of your budget, and therefore should command a large part of your design efforts. You don't necessarily have to spend a lot of money to get a nice, cohesive look. Just choose stuff from the same manufacturer or even better, from the same line. Yup, it's that easy. Manufacturers pay professional designers all kinds of money to design whole lines of fixtures that look great together, all so that you'll buy everything from one source. Why fight it? It's the easiest way to make your bathroom fixtures look like they were designed to go together - because they were! Now of course if you find a shower fixture that you're absolutely in love with and the matching sink faucet is pure garbage, go to a different line, and as a last resort, a different manufacturer. Nothing I say, including this, is a hard and fast rule. That being said, generally it's easier to source out a line that you like for all fixtures, rather than stitching it together from different lines.
Another consideration is the various material options that you have. Tile is not the only material you can use on the floors. Cork is extremely durable and water resistant when installed properly, and cork provides a nice, warm surface for your feet as well. If you're using tile for your tub/shower enclosure, you need to make sure the proper tile substrate is being installed. If your using a gypsum-based material, the only option is Dens Shield in my opinion. It has a protective layer of fiberglass that keeps the moisture out. Even better is to use a cementitious backer unit (CBU) like Wonderboard or Hardibacker. These materials are impervious to moisture, and even if your waterproof membrane fails, the wall will not disintegrate with exposure to moisture. To find out more about waterproofing and tile installation, check out my DIY series. For help choosing a contractor, read this.
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