I wrote this app specifically to not have separate child apps for everything: I wanted the same notification device, same schedule, etc., and didn't want to need to configure that separately for every single "group" of devices. (There actually could be some way to make this work by splitting configuration up between parent and child apps, I can actually see some value to having certain devices listed as "In use by" something that might give better clues as to what part of the app they are used in--but I'm not sure if that's your underlying concern. This would require some re-working, however.)
The good news is that if you do want entirely separate apps for whatever reason, you can already do that: just install another instance of the app, name it whatever you want, and configure it however you want. Nothing should stop you from installing multiple instances of the app (some apps do prevent this), and you can customize the installed name for each to make them clearer. They just won't show up as parent/child apps, just separate "regular" apps, but if you name them appropriately, they should at least appear next to each other.
This is a feature provided by the platform UI for parent/child apps/devices and other collapsible sections, not anything an app would need to do on its own.
This is something that could be easily added to the app -- a way to provide a description for the group besides just the number.
Thanks for the kind words! I think the only hint is a link in HPM, and I don't normally share unless people ask: https://paypal.me/bertabcd1234. As usual, I should mention that it is certainly appreciated but never required and also carries no guarantee of support, specific feature development, etc.