In my mind, some sort of graphical user interface that would allow you to query data and have the log system return results that are easily parsed. At the very least, have some sort of API that allows you to do this. The /query endpoint exists, but doesn't seem to return anything that's really fundamentally useful from a large-scale perspective.
I agree that the nice graphical tools available for Elasticsearch are super useful, but it seems to me that those are not a feature of the logs storage or query interface, but rather one of an external app (e.g. kibana) that queries the system.
It would actually be somewhat concerning to me if a system like Oklog had all those graphing and visualization features built-in; that would be quite some scope creep for a distributed storage engine :-P
I disagree. Elasticsearch itself is doing most of the heavy lifting. Kibana is developed in sync with Elasticsearch so that it always has the ability to use most of the features of Elasticsearch.
The nice visualization methods are a direct result of the aggregation abilities of Elasticsearch
Ways to query the data are important and on this newly launched pkg probably need some work (haven't looked at that side of it), but visualisation does not belong in a logging tool, it belongs in external tools querying that tool.