When going on the "/badges" page on a StackExchange website. All you are presented with a tick next to badges you have achieved.
In my opinion is perfect for badges that can only be achieved once, but for those you can unlock more than once, e.g. Enlightened.
Instead of just showing a tick on these types of badges, instead show a number in the green circle (or whatever design is applicable for the website).
I understand that this could cause problems if say the badge was earned #### times. In this case it could just show a +. Then if the number was shown on mouse-over it could say ("Earned badge 1643 times.") Leaving the UI nice and compact.