Phew! So right now Collections don't have a spot for descriptions, nor ordering alphabetically. Here's a Collection of all my Collections ordered from A-Z with a short description of each one.
If you're still unfamiliar with Collections and how they work, you can check out my overview/tutorial on :
h/t for the idea, if you want to mirror this all you have to do is create a new Collection and then share each Collection to the new one and voila! Afterwards, you can share the new Collection to your PUBLIC circles and pin it on your profile for easy access.
TIP: uncheck the "People that have you in circles automatically follow this Collection" while you are filling it with other Collections. Once you're done, re-enable this (should prevent a flood of shared Collection posts in their streams).