Slicing data

I'm noticing that there are always multiple ways to slice the same set of data. It seems that there are many layers of data--- from the broad policy and its roots and shoots, to the various aspects of schools and instruction, and the individual actors at different times and places.

I've been slicing some data for the past few weeks (special thanks to Excel pivot table and charts) and could literally analyze the data in 100s of interesting ways. How to decide how to analyze your data? How much of the data analysis should be planned before collecting the data (for future reference)? How do you stop the data analysis and feel confident that you've figured the situation out? What if you slice the data one way and fail to discover a fascinating story hidden under other layers of data?

For another project, we're layering some interesting theory and could add our data (that would be the frosting on the paper), or we could craft a purer and deeper conceptual paper. Most papers have their intricate layers, and it's tricky to figure out which layers are of interest and work best with the theory, the methods, etc.

So many delicious options!