When working with high level initiatives that span many quarters, current view demands lot of scrolling (using Quarter resolution). The quarter scale shoud be compresses to allow the full span view in a single page ideally.
|Release time frame|
This is possible today through the use of timeline controls. You can set the start/end date for your roadmap, as well as time scale. You can read more about it here: http://blog.aha.io/perfect-visual-roadmap/