Ticket types in Zendesk are limited to incidents, problems and questions. Incidents and problems are well documented with their origin in ITIL. But questions are a bit off. And what about service requests?
According to ITIL a key component of a service desk, is the ability to handle requests for services (service requests) defined in a Service Catalog. The service desk should then offer workflow that supports the process of the procurement lifecycle.
Sounds familiar? Basically it's a shopping cart or e-commerce solution. And we're not sure if Zendesk needs a shopping cart feature. We're not certain either that we're any good at building such a thing. We would rather investigate what on-demand solutions are in the market, and see if we can leverage the necessary integration to make it work smoothly without compromising the functionality.
As for the ticket type questions, we found it necessary to add a type for all those requests that aren't incidents, and that you don't want polluting your metrics or SLA compliance. An FAQ consolidation engine could be a perspective leveraging the ticket type.