In regard to this idea, "Advanced Filters not just “Is” but “is not” or “is” +“also is”
Would suggest that advanced filters allow not just searching for what “is” - e.g. a custom field is a certain result
But also allow it to say I want a filter based on the exclusion of one or more results e.g. a filter that allows me to exclude two single-select custom fields.
For instance, I have a single-select custom field for a customer list. In that list, I might want to filter out two different customers. So I’d need a more advanced filter to do that, and the view would leave all customers EXCEPT those two customers.
Similarly, it would be nice to create a filtered view to allow ONLY those two customers, filtering out all the others.