A great extension should be to add the ability to select some @IP in the result list to add them to a pinger extension.
What do you think of ?
Then you could add a realtime statistics result on this specific list for how many pings have been sent/received, plus a ratio to inform us about the availability based on that information.
Then this tool would be all-in-one swiss-knife.
If it not possible for the moment, i could suggest you to add a refresh check-button (with an optional intervals setting) to the existing version. But this solution do not focus on the expected nodes selected in a pinger extension. This could be a first stage before this extension.
The network scanner is not a host monitoring tool, but if you just want to monitor link to a specific host, I'd recommend to add ping as an external command (see attached screen shot). This extends the network scanner with an additional pinger command.