PHP Snippets / Building a module using a pre-existing view

Forgive me if this is a dupe. I've searched.

I have attendance records, in the form of a bunch of nodes containing fields like "date" (date field) and "attended by" (user ref). I want to create a leaderboard, showing which users have the best attendance rates, within a specified time span.

Approached I have considered:

1. Use Views calc, make a separate view that takes an argument for each user, then combine + sort those on another page somehow
2. Use a PHP snippet somewhere to interpret the data returned by the view
3. Write my own module that uses the Views API (and uses the attendance view I've already created using the UI)
4. Write my own module entirely

I'm thinking 2 or 3 are the best options. How would I go about doing that?