I'm suggesting a new command be added: /Quota
This command would tell you the status of your current Quotas in a format similar to this:
Coal: XX/XX
Iron Ore: XX/XX
Redstone:XX/XX
Lapiz Lazuli: XX/XX
Gold Ore: XX/XX
Diamond: 16/16 57:56 Until Quota Resets (<- The Time Left would only show after you've reached the quota)
(Not sure if all of these actually have Quotas, but w/e, just an example)
I think this command would be very helpful for those that mine a lot.
Also Adding onto this, maybe the server could Automatically send the player a message when a Quota is Reset, e.g. "Your ____ Quota has Been Reset!"