I would like to propose an additional improvement of usuability in the Scope view of JIRA Portfolio 2.0:
After pressing "Calculate" one indications of errors as exclamation marks attached to each affected issue. Usability is limited in two respects:
Both aspects make the phase where one fixes all the scheduling issues cumbersome and error prone (because you eventually might oversee one of the errors).
Proposal would be to have a dedicated view or filter for explictly showing the errorneous issues allowing to tackle them directly.
In general, however, the tool is great!