Background: I would like to focus on the set of people who are first cousins of (my) ancestors at each available level of the hierarchy. This helps me check contemporary family activities, vetting local records and documents for close family members who may be mistaken for one another. It also helps me follow "shells" of 2nd, 3rd, ... cousins who may wish to share information about common ancestors.
Question: Are these or similar "cousin-centric" relationships addressed by some specific software products, or by some specific thoughtful bloggers? (I can read math and computer science formal languages, so geeky responses are fine.)