Regarding messages & notifications
I think it would be better if, when you click on your notifications along the right side of the screen, that a left-click simply removes the message, while a right-click removes the message & centers you to whatever the message was about (city, hero, etc). So after being told your Mine is done, you can either clear the message or clear it and zoom to the city.
Also, it would be great if you could TAB to the next city or unit with the city production window open, without having to close it first. And what exactly is the 'build' button supposed to do? It's not needed, so far as I can see....