When it's neccesary to query multiple indexes - for example, to fetch metrics on an index page it's neccesary to make a large number of queries which can be slow and unreliable over consumer internet connections.
In my use case, we need metrics from two event streams/datasets so the number of queries is now doubled.
One index page of 20 entities now requires 40 cached dataset queries where it seems the bulk of the overhead is in the http connection between client and keen.
The ability to request multiple index ids in one request and receive the result in one resultset would greatly improve this experience.