I'm not sure if this has been suggested before... probably... but it would be nice if, during the time when the Main Hall is upgrading, we still had access to the tab that shows numbers of relics, production boosts, etc.
Can you press hotkey "S"? I forget whether that works or not. Either way, another method of viewing that would be nice. I bet most players don't even know all of the hotkeys (it took me 2 tries just now)