Procedure:
  1. Identify current issues with the job. These can be issues of balance, applicability, or gameplay. Note if and when a gameplay element affects one section of players negatively and another section positively.
  2. Identify reasonable expansions into further toolkit themes, functions, or gameplay mechanics that you'd find attractive (and expect most players would, too).
  3. Include the likely most attractive of the above expansions in the course of or alongside fixing the above existing issues.

Have at it.