Hi Daniel.  In regard to the issues you mention

• not really being per-job,
  

  Both are supported by Perform since v13. 
  You can assign activities to users by job audiences and have the activities (Appraisals) change as an employee's jobs change. 
  You can use multiple jobs and multiple assignments via posns/orgs and Audiences, so can have activities for internal teams as well as jobs.

  and 
• not recurring.
  There's a lots of capability around repeating activities (v13 enhanced in v16).  You can trigger the next activity based on a number of different triggers at many different periods. 

• Reporting.  Reporting is a bit different in Perform.  I'd discuss your requirements with your partner.
• Types of content.  All the content types available in Learn are available in Perform.  Notably the redisplay and review content types are considerably better
• handling of changes in manager.  This is available in v16.  All relationship types in the Job Assignment can be dynamic with choices about how the outgoing user's participation is handled (close it / leave it for them to complete).  We also support the Temp Manager relationship in v16.
  

Hope that helps