Register a site: add fields to measure "net promoter score" of CiviCRM and partner
On the Register a site form, add two fields to measure:
- On a 1-10 scale, how much would you recommend CiviCRM?
- On a 1-10 scale, how much would you recommend this partner?
While people who fill in the Site Registration are biased (they're continuing to use CiviCRM), it's still a indicator of their satisfaction with regards to CiviCRM and to their partner.