Yes, we are guilty as charged here. We yet make it easy to extend textual data from the devices. It is planned (but not scheduled yet.)
But, there are two workarounds, one more kludgy than the other...
The less kludgy one is that we may already be collecting the data (e.g. the sysinfo on network devices usually includes the software version. This is already collected, and you can run a report on this. Its visible in the system tab on the devices page.)
The more kludgy one is that you can write a datasource, which discovers the info you want via SNMP, and uses that as the name for an instance, but doesn't actually do anything or collect anything on that instance. I can provide more details, or an example, if you want...
