GNOME Logs is keyboard navigable (thanks!!) but there are a few things which might improve it:

1. Tab should move you between the list on the left and the associated log entries on the right (i.e. and not within either list). That way a user could Up/Down Arrow to the desired log type and then immediately jump to the associated log list.

2. Alt+Left should do the same thing as clicking the go-back ("<") button. (gnome-control-center and gnome-software do this)

3. Consider automatically updating the list on the right as the selection on the left changes. While you can cause the log list to be updated by pressing Enter, that you need to do so is not immediately obvious. And in other apps where there is a list on the left and associated content on the right (e.g. Evolution), the content on the right is automatically updated.