Imagine you have a series and you know for sure there will be a specific release because they do basically everything (we all know those). But you don’t want that release if you can have a better one that may or may not come. Having a tool to download one release and upgrade to another release if it becomes available would solve the hassle to manually monitor the releases.
When you use multiple tags the “searcher” will show any download that satisfies all tags simultaneously. A more versatile way of handling this would be to give tags ranks/groups. If one group of tags finds downloads that satisfy all requirements these downloads can be different from another group of tags. If you could rank these groups you could use that to choose which release you prefer. The “searcher” will search for downloads for all groups. If multiple groups have downloads the “searcher” will only pick one from the highest ranked one. If all groups have the same rank it would basically be the same as now.
The scenario i have in my head:
Set the tags for the fastest or most reliable release and give it rank 2. Make tags for the release you would want more but you don’t know if they deliver releases and give it rank 1. If a new episode becomes available rank 1 tags will most likely result in no satisfying results. But rank 2 will. Later when sonarr searches for upgrades rank 1 will find satisfying results. Since they are higher ranked sonarr will download the new release.
Another effect would be for releases that may not be as reliable. If there is no release for a single episode the “searcher” would dodge to a lower ranked tag/group to avoid not having an episode. You can do that with choosing your tags to search for multiple releases but then the “searcher” will choose a random one but you might (and most likely will) rank/prefer releases above others.