Redmine

We devised a plan to implement our Scrum methodology into Redmine. We are planning to create at least 3 new trackers called "PBI", "SBI" and "WI" (Product Backlog Item/Sprint Backlog Item/Work Item). The WI won't be a real tracker but instead it will be a parent virtual tracker group which includes "Bugs", "Tasks" and maybe as a separate workflow "Tests" etc. This structure covers our needs but there is an essential missing control mechanism which is the ability to tell Redmine which tracker should be followed by which one. I'm thinking of a workflow-like mechanism which covers the transition rules of trackers. First come the PBI trackers, then they go into sprints as SBI trackers and SBI trackers do include tasks, bugs, tests etc which correspond to WI trackers. There may not be a transition between SBI to WI. Normally SBIs are just an upper group of WIs. So we don't just need a workflow functionality for trackers but maybe a hierarchical grouping function, too. But we could also live with it if this wasn't supported. It only would change the filter parameters for SBI and WI reports/Gantts etc.

Is it possible to implement something like that in Redmine or should this be a feature request?