Most of the time I use RSS, the individual items in the RSS-Feed are released by some kind of schedule.
Eg. I could have an entry in the RSS-Feed tab for the Feed URL "xyz" and Filter "abc" and know for sure that a new item will be published to the RSS every Friday at about 18:30.
If I wanted to get the magnet link and download the torrent as fast as possible, I'd have to set the feed update interval as low as possible. Unfortunately that would increase the traffic to the RSS Server all week round even tho it's not needed most of the time.

My idea would be to add something like an expected release time. The client's RSS update interval would be really low most of the time until the the expected release time is reached (or slightly before). Then it would increase the update to something like a minute until a new transfer is added and then go back to the slow pulling interval.
You could also add a sortable expected release time column to the RSS Feeds view.

Try the Scheduler, you can start/stop RSS feeds with it. I know this isn't exactly what you need but it may be sufficient.