Redmine

I see various issues\features in redmine bts, but none of them match my goal.
I have a redmine installation that serves both the developer teams (2 different agile team) and some customers.
Using both native visibility workflow in redmine and after creates some cutom plugin I can control with great granularity visibility\mandatory field on developer side and on customer side for all projects.
I have encountered only one problem and this is related to roadmap management: I have multi-projects shared version, because I use version to define sprint and project-backlog.
The problem I have encountered is that also if I can hide private bug of projects to my customers, I cannot hide the shared roadmap.
This for me is a defect because redmine should be more, nativilly, more scrum oriented.
(I see a lot of plugins but none of them match my requirement)

Thanks in advance.