Cards should support something similar to the SQL "HAVING" clause

I often want to visualize some of my metrics, split by a field with many different possible values. This might result in hundreds or thousands of series in my chart, which is slow and unreadable. I'd love to be able to add a filter that operates on the aggregated values (similar to using the "HAVING" clause on a SQL statement, rather than the "WHERE" clause), so I can filter down those series based on the data.

As a theoretical example, I might want to look at revenue by customer, but I have thousands of customers, so I'm interested in only seeing customers who bought more than $1,000,000 for each day. I'd like to build my chart with x-axis of day, y-axis of sum(revenue), and series split by customer. Instead of showing all 1,000 customers with that configuration, I'd like to be able to create a filter that checks if sum(revenue) >= 1,000,000.

This would allow me to visualize an importent subset of my data without knowing beforehand who will be in that subset (discovery vs. already knowing).