I know you can see the production rate of all and individual buildings via the Economy Overview. I think it would be also useful to be able to see it when looking at buildings. Something simple like the atached image.
That is just an example but anywhere on that view would be useful. This way you can see on any building you look at if it is doing OK or not without needing to go into the Economy Overview and try and find that building from the list of the ones you have.