As a Kibana user, i would like to be able to tell what version of Kibana i am using, so that i can look for appropriate documentation, file bugs appropriately, etc.
Discreetly including the version number somewhere on page, perhaps in the footer, would achieve this.
It is entirely possible that this is already implemented in the current version of Kibana, in which case i apologise. Sadly, i do not know if i am using the current version of Kibana.