Groups have been expanded to have a binary state depending on their members. However it would be really great to extend this to non-binary values. For example, a group of temperatures could take on the mean value or a group of power entities could take on the sum of the entities. Maybe the Min/Max extension could be leveraged.
If groups allowed for templated attributes, then I would think anything could be added. Like a group of lights and you count the number of lights that are on divided by the number of lights in the group would give you “percent on” … your examples would be just as easy. So maybe the real question/statement should be “Allow Groups to have templated attributes”
One advantage is that it completes the “Group” enhancement. If I’m already building groups of motion sensors, etc then I might as well build groups of temperature sensors, etc, which currently all have the state of “unavailable”.
At the moment I use Min/Max sensors to create an average temperature for my kitchen, basement, house. Maybe I missed it but I can’t create a Min/Max sensor for motion. Templates work too but can be bulky with lots of repeated code.
Multiple ways of doing the same thing is fine - user/situation choice - but let’s be inclusive. Groups of similar things could have a real combined state. Likewise add a on/off/true/false function for Min/Max.