Selective revision delete

The revisions feature is nice, but as many people have mentioned in various other forums, it creates tremendous waste in the database. I’ve seen instructions for turning revisions off and for deleting all revisions, but I’d prefer to use the feature like an OS or email client “trash” bin – it’ll save things until I decide I don’t want them. Given that, I’d like to see some features for selectively deleting revisions. Two methods come to mind:

1. click-to-delete; the most obvious method. Directly delete selected revisions
2. retention policy: Delete all revisions more than X days old and/or more than Y revisions old. E.g. maybe I want to keep revisions only from the last 3 months, and I don’t want to save more than 10 at a time.