CRM Systems – Case Types Best Practices

We’re currently using Remedy as our CRM for internal user case/ticket tracking. However, the categories and case types established in the past are too numerous and prevent the team from accurate and consistent categorization of support issues. Is there a resource available to review Best Practices for establishing a simplified, yet effective, categorization of support issues? I welcome any feedback and am willing to share ideas on Support/Help Desk management in return.
Thanks~