I can answer some of these points. Firstly there’s no way to delete a Look from the content validator view.
Next it is indeed possible to delete a look on the Look page by clicking the cog in the top right-hand corner:
There is also a way to examine looks. You can use the i__looker/look explore. Link is
In the explore filter on look.deleted_date is null for all non-deleted Looks.
You can add look.id, query.explore, query.model, query.formatted_fields, and query.viz_config to find out info about explore, model, fields and viz used in the Look. A sample URL would be
Unfortunately I don’t believe there’s an easy way to filter to the Looks shown as invalid by the content validator. This feature would be a great addition. But you can filter down to specific looks after getting the IDs from the content validator.
There are plenty of other fields you can add too, I encourage you to have a play.