Map packs?
I really don't feel like separately downloading and installing hundreds of maps. Are there any good packs out there? Preferably with some way of knowing which maps have and have not been played.
There are some map packs released by some of the members of this community.
In the menu left for example there is a community spotlight called "12 Angry tests" This is a very nice mappack, containing 7(?) maps made by CaretCaret.
If you just want a quick selection of some good maps, make sure to check out the community roundups on the main page. These roundups contain the best maps released in a certain amount of time. So downloading these maps will certainly give you some very very nice maps.
To create a .zip file or other way of packing maps together community members made isn't really a good idea since you should ask them all for permission. Stay tuned, 'cause various members of this community are currently working on quite a few different mappacks/mods. (I can think of about 5 mods currently being worked on by active members of this community)
As a response to your question, I created this thread of my favorite maps. Since it's not feasible to create map packs, a series of links to some good maps is the best we can do.