I'd like to do that, not sure how possible it is though. `LastDatapointSummarizer` doesn't use an aggregator, why `AggregatingSummarizer` does. It would be possible to make a `last` aggregation method, then do away with `LastDataSummarizer`, but the separation is intentional. `LastDatapointSummarizer` is faster than `AggregatingSummarizer`. It might seem a bit unnecessary to have such small optimizations, but given how intensive metric summarizing is on CPU usage, I think it helps a bit.