Hi Sergio -
It sounds like you've been looking at our Workflow function, that's great! But I understand what you are saying. We don't have any additional "tabs" on the road map just now.
We have the ability to automatically create a Defect from a Test Case; a Test Case from a Defect, and a Test Case from a Requirement. Everytyhing is automatically linked together.
Personally, I like the idea of creating anything from anything and I'm pushing for that as an enhancement - I'd love to create a Requirement from a Defect. So I'll add your request to mine so we know there's interest.
Thanks!