Thinking about design a bit more, but overall I really like the idea of being able to do this.
For instance, I wanted to merge some of the music communities in Lemmy.world into 1 feed for a playlist. So making a Loom to act as my little music visualizer for all of those is nice.
Furthermore, there was a user who noted “This is why users need the ability to group multiple communities into supergroups” by @LazaroFilm some time ago. I feel this resolves that.
They also did not like the idea of this setting being platform specific. So down the line, finding a way to create a sorta schema to share with other developers would be cool. Or the other way around, where other developers were to make one, Loom could adopt.