The mod wine bar is a great project. I made a mistake cutting the inserts forcing me to use extra 1/4" plywood, so I decided against putting a back on the hutch or a cover to the bottom of the base. I actually like the way those both turned out.
After reviewing the Pottery Barn collection, I decided to put a bottom on the hutch. I think it is more stable this way and allows greater flexibility in the future (since it is not attached to the base).
The one modification I would like to make (and potentially will make in the future) is the stemware holders are just slightly too small. I would modify using a 1x4 rather than a 1x3 for the two middle pieces.
I am extremely pleased with how it turned out and look forward to building two more in the future.