First of all thanks for providing new stats API, especially all the stats related to pipeline processing.
This is super awesome! I already made a lot of improvements by investigating biggest time consumers.
I have one suggestion however; could you consider possibility to add custom names/aliases for those rule stats?
Why this may be good you ask? I'm working on LS Diamond collector similar to ES one from https://github.com/python-diamond/Diamond/tree/master/src/collectors/elasticsearch that will graph all of those stats, but that won't be very useful for pipeline stats shifting names with any config addition.
So having a (possibility to add a) consistent name here would help a lot to keep/analyze some long-term metrics.