It would be nice if the MangoES configuration module exposed some of the Ubuntu package update settings (in the same way that it allows you to adjust the network configuration) but -speaking personally - I don't really feel that network monitoring is something that should be part of Mango's scope nor something I expect Mango to try to do.
That said, in the same way that the MangoES units come with Webmin installed (which is hugely useful) perhaps they could come with ntop preinstalled too, if the license permits that. Not sure if the ntop database size would be an issue.
In any case, ntop is a useful tool for any MangoES administrator.