Most useful options for git shortlog, using “Pro Git” book repo as an example.

-n, --numbered
    Sort output according to the number of commits per author
    instead of author alphabetic order.

-s, --summary
    Suppress commit description and provide a commit count
    summary only.
           
    ... snip ...

<revision range>
    Show only commits in the specified revision range. When no
    <revision range> is specified, it defaults to HEAD (i.e.
    the whole history leading to the current commit).
    origin..HEAD specifies all the commits reachable from the
    current commit (i.e.  HEAD), but not from origin. For a
    complete list of ways to spell <revision range>, see the
    "Specifying Ranges" section of gitrevisions(7).

[--] <path>...
    Consider only commits that are enough to explain how the
    files that match the specified paths came to be.