The only fields that I don't use right now from Membership.csv are "MRN", "Endowed", "Rec Exp", "Mission", "Spouse Member", "Sealed to Spouse", and "Sealed to Prior" - basically, the temple and recommend information.
The age is stored as a floating point value, so the birthdate could conceivably be extracted (though it would take a lot of work to do so). I originally stored the age as only an integer, but doing so was inadequate for the nursery/primary divide.
I have considered adding a filter, "Likely Active", which would include people who:
- Have a current recommend
- Have had an ordinance recorded within the last two years (excluding baptism but including confirmation)
- Have recently returned from a mission
- Have a family member who matches any of the above
I can see this being a big help to (e.g.) newly called EQ presidents, who need to create home teaching routes but don't know who they can call. Unfortunately, there are risks associated with this if people take it too seriously. It would be far from infallible - just a nice starting point. Anyway, I've tested it and like the results, but I'm not sure I'm comfortable releasing it....