Designing and remodeling a garage can be very rewarding.
I like the fact that you are using blk/white/grey in the tiles. Remember that the darker colors will rob you of light and the white is tougher to keep clean. I like light grey as a compromise.
The first thing I did was repaint the walls and ceiling white and install as much lighting as possible. I like T8 fixtures.
Also think about what activities your garage should accomodate. Oil changes, detailing, relaxing? Design around that.
Storage is also very important. Use your wall space.
I have some older pics in my gallery of my garage so far. Still not finished with it.
http://autopia.org/gallery/showgalle...0&ppuser=16079