I ... I want to give you a hug. Setting up Nagios is pretty much my least favorite sysadmin task by far.

Also, I, personally, am not bothered by curl installs. The fact is that a lot of software not available in a distribution's package manager is installed that way or similarly. It's assumed that the sysadmin will review what they're running. A better method is always good, but curl installing is no big deal, for me.