Quick tip: if you need to grant access for your data guru who needs to see and be able to modify everything in the Insights module, you should assign them the data role.
need the Manage Data permission.
need Access Insightboards permission for viewing.
if a user with 'Access Insightboards' has a custom insightboard permission to edit and update a particular insightboard, they will be able to add tags, change its name, and re-arrange the insights. They won't be able to enter into edit mode of the insights and execute queries, nor will they be able to see any other insights than the one in the insightboard.
to view insights, a user needs Manage data.
this permission also gives them the right to execute queries against any data source you have connected.