Consider the following situation…
Assumptions
0 voters
The last one is “Total Volatile Organic Compound”, I can’t modify it anymore.
As a default, I would use a capability which is NOT Available for other types of sensors, probably fine dust, 2.5 PM, which is one of the most common for an air quality detector. Or TVOC, which might be considered the most serious. 
But that said, I think it’s inevitable that different people will have different preferences for this. I don’t think there is a “best,” because I think it just depends on the use case for which a particular detector was purchased. 
I’d create them as separate child devices…
I thought about it, but I am trying to keep different profiles as much compatible as possible.
I use a generic way to create child devices.
It works well only when each child is in a separate component.
To make different profiles compatible, I try to concentrate most capabilities in the main component.
So I would need to think another generic way to create child devices from capabilities of the same component.
And it probably would require a complete rewrite of profiles, which would demand a different driver because the old profiles wouldn’t be compatible with new ones.
For my case, the parent/main is usually a switch, light, or similar. It is possible to attach multiple sensors, and sensors of the same type (e.g. multiple temperature sensors). So it’s not possible to use multi-components.
A parent with multiple child devices (1 for each connected sensors) is probably the easier way.
I’ve been puzzling over this recently…since I added an Air Quality sensor to my mix, and along getting relevant info to get displayed somehow… have it control my air purifier (especially at night, it goes to sleep in auto mode when all the lights get turned off. But, I could manually control the fan speed, etc. But, trying to figure out how that should get done… Plus there are issues with SmartLife scenes, they report as incomplete so its hit and miss on whether they’ll respond from SmartThings. And, going through IFTTT is also hit and miss… but that’s what my IR remote device is connected to.
When I initially set up the Air Quality sensor, it was showing CO2 on the tile, which was reasonable…but as things updated, it has switched to showing temperature on it…which is the least useful thing, since its near my Aquara temp/humidity sensor which is one of two sensors that control a fan and a humidifier.
There is one problem with the sensor though…it periodically maxes the pm2.5 (~8743)…hmm, wait, now its showing pm2.5 on the tile. Though probably need to find a proper edge driver for it. It’s using the 0xEF00 Tuya Cluster driver. (oh I see, the driver recently updated on Saturday.)
The Dreamer
That’s right. Since last saturday.
Now if smart things would open up the air care app to devices other than Samsung’s overpriced air purifiers this integration would be perfect