It might make sense to add keywords (aka tags) into the metadata. Previously with the 1:1 mapping of desktopfile-appdata file we were kind of able to infer relevant tags from the desktop file, but since we can now have multiple launchables that doesn't necessarily work anymore. Yet I think it would make sense to provide the ability to set keywords for a component such that it may be more easily searched for. This is pretty much 100% analogous to the Keywords entry of the desktop entry spec. This would also improve reuse of appstream data to feed into the window store metadata (which too does have a keyword system).

<keywords>
<keyword>partitioning</keyword>
<keyword lang=de>partitionierung</keyword>
</keywords>

or some such