Please, do not dumb down the CLR just because it's now running on toy operating systems.
Live eventing is all about what's happening now.
Performance counters are about what happened and how much of it. That's why there are Avg and % performance counters.
I'm currently working on system/service/application monitoring systems and Windows and proper developed Windows applications are very easy to monitor by taking samples of performance counters and event logs.
I'm not saying how it should be implemented, but an "eventing system behind a pluggable adapter" seems to be a good option. Just don't forget to supply the ETW, EventLog and Performance providers Windows DevOps have been relying on for a long time.