I'm wondering if it would be simple enough to enable a Tuners In Use counter line item.
In the Tuners section of the app (all platforms), a simple section that tells you how many tuners are currently in us (live TV and currently recording) and how many tuners in total exist on the network. So in the pictured example, 2 tuners in total are in use and since the only model on the network is a single Extend, the app knows that counts as 4 total tuners, hence 2 of 4. If the setup was, say, two Extends and a Prime 3-Tuner, the same scenario would read 2 of 11, etc. Having it displayed on screen, especially for families, would be great rather than playing a guessing game or checking my.hdhomerun.com.
EDIT: The Extend is obviously 2 tuners, that's what I get for editing an image from Google and not taking the time to think. The "of 4" would be "of 2" and the additional setup example "of 11" would be "of 7", but you got the idea.