So not sure if you are done with this feature or not but I noticed that unless you check both chats constantly there really is no way to know if someone from your home city has posted a message there. My idea is to maybe add something that blinks when there is a new message in the city chat. It could also be something that could be toggled on and off. Also maybe you could make a toggle choice on if you want city chat or crew chat to show up on top. This is my first idea for the suggestions thread so bare with me if I am missing something.

What is your idea? - To add a blinking icon when someone puts up a message in city chat
Has your idea already been suggested in some form or another before? (Check the Suggestions forum for past threads with ideas the same or similar to yours.) - Well its an addition to the city chat idea
What does your idea entail? - Admin adding some sort of icon into the game that blinks when a new message can be read in chat
How can your idea be successfully implemented into the game as it stands? You could make that eye have another icon near it or even use the eye itself. Its pretty lonely on that bar.
What major changes would be needed to make your idea work? - Not much i dont think
What is the positive impact of your idea? - People would be able to know when a message is posted in the city chat and not have to refresh every so often to check
What is the negative impact of your idea? - People may not like the blinking so to counter that I feel like you could make it so we can toggle it on and off in the options
How may your idea affect the rest of the userbase? - Cities will be able to be informed by city chat any information that needs to be known city wide and not miss the opportunities presented there. 

LOVE THIS IDEA!

I was actually on Suggestion corner to suggest something similar, but I like Fydora's idea better.

Bruiser gives it two thumbs up!

Love it. Citizen's sponsor ftw!

I think this is a planned addition already.

And if not, it should be.