Ability to assign multiple custom roles

It is currently only possible to assign a single custom role to a user.

As an admin, I often define multiple distinct custom roles with very specific permissions. For example, a custom role to administer capacity planning and another custom role to configure integrations. There are cases where a user should only be able to configure integrations, but there are cases where other users should be able to both configure integrations and administer capacity planning.

I would like to be able to assign a user multiple custom roles when applicable. In this scenario, I expect that Aha! would ultimately add all the permissions together across the selected custom roles.