Maybe it would be better, depend on how it would be implemented, the good thing with lists is that you can create many of them and they stack one under the other which means that theoretically you can have thousands of them, the categories are oriented horizontally which is limiting, you can't have as many as with lists placed in that arrangement even if you implement something like drop-box element.
At any rate I'm not against the feature, i just posted about list in case you didn't thought about using them.