Hi,
Those look great.
Regarding coloring the handles I remember you mentioning white handles to match the white cabinets in another thread (I think you posted a pic?). The first thing that came to mind was, that white might show oil, grease, dirt, etc. a lot easier and be harder to clean aggressively if needed than the base aluminum handles, though that is a cool monochrome look and idea.
If you think black is too much of a contrast to white (although an all time classic combination), perhaps you could experiment with a few dark grey shades to soften the tone and contrast with the white/ off-white of the box. I'd (and I probably will) go with white walls or light grey walls. Different shade of grey floor. That way if you ever get other things that come in different colors in there (red sandblasting cab, purple top box?) it will still work, compared to having to work with browns & beige. I'm sure once you're done you will be smearing your hands all over the place as well as dancing around like a happy puppy! Followed by more box fondling.
I'm currently in the pre-production stage of my garage as I start to see what I have to work with as I gather tools and boxes. Thanks for posting this. Looking forward to your progress pix and final results.
Thanks.