Templates allow you to define a specific structure for data, and then implement several instances.
Partly the advantage is that, if you transmit "names" rather than aliases, you translate the instance name once, and then just the member names.
Additionally, there are some Object Oriented advantages, for example making faceplates that require a particular template as input.
FB_Metric should be able to have one FB_Template... which needs to be able to have several FB_Metric :D
FB_Edge needs to be able to xBIRTH
FB_Edge needs to be able to send xDATA
FB_Edge needs to process xCMDs
FB_Host needs to be able to process xBIRTH
FB_Host needs to be able to process xDATA
FB_Host needs to send xCMDs
FB_Host needs to process xDEATH
The user will want to be able to efficiently link these to DUTs (both in the Edge and in the Host). That might be a 188.8.131.52 feature, but thought should be put into how this might be realised.