At the moment (v6.1.3) there is the option to save snapshots in daily folders or category folders.
I find the latter more useful, as it is then easier to compare how a given parameter has changed over time, because all the time-stamped snapshots for a particular category are collated together. Since I am only saving 24-hour snapshots once per day I find it a great way to get an overview.
I can understand that data saved after each sample might be best stored in daily folders, but if the ability to save daily snapshots by category is retained, I think it's easier to identify which day & category should be examined at raw data level.
Just my personal opinion...