I would choose #1 as you really don't gain anything from #2, and #3 is less scalable, which may or may not matter to your situation.
However, for the initial loading, I would lump all the data-sets "together" (see below). IMO, This decreases usage of and reliance on the most likely point of failure.
Store each data-set as part of an array, because sorting of non-indexed data types like Object
is messy and unintuitive. Array
is a huge help when managing the "timeliness" of data-sets.