Hello MarkCanada,
Thank you for bringing this up again and for providing detailed feedback!
We understand how useful rules-based features like coloring emails, assigning specific notification tones, or filtering based on sender/header/body content could be. These suggestions have been on our radar in the past, but implementing such advanced filtering and notification features requires significant development resources to maintain compatibility across the diverse email protocols and services Aqua Mail supports.
While these features aren’t available currently, we appreciate your input as it helps guide our future development priorities. We'll add your suggestions to our user wishlist for consideration.
Thank you for sharing, and we’re grateful to have users like you who are invested in making Aqua Mail better!