Rather than create a bunch of custom fields to answer questions I think a template that adds text to the Body of the ticket.
The templates should be assigned to catagories so they are restricted. I would imagine a dropdown with available templates and text to copy template to body.
For example a ticket to grant permissions to accounts in our financial software would look like this. Just fill in the blanks...
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Activity Center:
Org:
Object:
Project:
Assign to Role:
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