According to all I've read about Scrum, having one globaly ranked backlog is key. While I like ordering the User stories into Themes for clarities sake, It makes the absolute ranking of the backlog a task that needs to be done ouside of your great app. Any chance this is a feature you are working on? I could use only one theme to have a global rank, but that also would name all my user stories like the one theme which wouldn't be very helpful too.

It would be nice when we can filter the backlog with a custom query. For example with a keyword authorisation, I expect only the items with the keyword in the US / acceptance criteria or comment. 

It looks like that the 'Stats' tab only works after a completed sprint. This implicate that the stats tab always works for the last sprint and not the current.

We would appreciate very much if we could add text to a theme (e.g. a description / motivation / story / use-case), such that everybody can read what the contained stories are expected to sum up to when completed.