For example, a good picture to illustrate ZK proofs. Should I ask on the SE? Or in the Meta-SE?
No, this is on topic on the main site, cryptography. If asking for descriptions of cryptographic primitives is OK, then I don't see how asking for graphic representations isn't.
That said, just asking for tools or other resources isn't. We're not a human Google. Basically you would have to ask how you could draw a specific algorithm and make some effort to do it yourself before that. Only ask about where you get stuck drawing the primitive.
If there are already pictures about ZK proofs around, then please explain what is missing from them.
In other words, you can ask for graphical representations and such, but you would still need to take some time for your question to be on topic.
Meta is definitely not the place to ask, as it is about how the site operates. And you can always ask in chat, but you might just get chatter or nonsense back from the other participants.
Asking for clipart is not good for our site. We are not designers or looking for pretty pictures. I'm okay with some Tikz questions, though, not sure about the reputation badges;
- You have gold in illustrations.
- You have silver in illustrations.
- You have bronze in illustrations.
doesn't sound Cryptography, right?
In my opinion, in general, this is a chat issue and most of the time the OP's will have a reputation to talk there.
So, I say NO