@billcouper I 100% agree with you.
I will add to this that it would be amazing if RX and TX nic/SFP errors could be made visible in the interface as well. reason why i mention this is we recently had a problem on one of our hosts storage links where due to a dirty fiber we had some problems (vm's going to read only, crashes, very poor IO). Due to how dom0 sits as a VM we could not get stats off a nic using ethtool or snmp. It took WAY to much trouble shooting to figure out that our issues was caused by a dirty fiber on the servers side.
the more native/local self monitoring/alerting xcp-ng and XOA can do, the better.