Actually, that would be a great idea, especially where WiFi is concerned.
I have found with the built-in wireless on an RPi3, you suffer from a lot of dropouts and even when adding a USB wireless dongle, wireless does not perform all that well.
I went as far as installing a WiFi Extender and while it did improve things a lot, it still did not eliminate the dropouts, for me at least. Now, I am connected by both Wireless and Ethernet and the network performance is very good indeed, no dropouts at all.
I only have the built-in wireless connected because I am not sure how to disable it correctly.
Anyhow, having some sort of graph or numerical output to show connection speed or signal strength would definitely help track down any connection issues someone might be having or at least allow you to report good/poor network performance.
Nice one Frank!