It would be really helpful to have the option to display a column with a contact's list memberships in both the "Contacts" page and "Lists" page. This would allow you to quickly see if multiple contacts are or aren't members of a specific list.
This is a much needed feature. How do I know this? There are 4 total tickets asking for the same thing and I came here today to submit my own request. This should be SO EASY to create and would provide huge efficiency gains to anyone using Lists in Hubspot.