Fine grained control for auto moving articles to the trash

[Tyrone Bronne]

Looking through the preferences I only find a global option to automatically move articles to the trash.
Usually that it is not what I want.
However, from all my subscriptions there are maybe two dozens creating such a high volume with their feeds that keeping them all around forever is wearing Vienna down and wasting space.

– Is there a trick to instruct Vienna to delete articles automatically after three weeks for individual feeds while the global option stays at "never"?
– Is there a trick to instruct Vienna to delete articles manually from individual feeds with an option like "all older than three weeks"?

If not, these would be my feature request.