When writing these blog posts, I usually create a single circuit with a bunch of disparate parts - I don't need the circuit to be functional for any simulation purposes, I just need the diagrams and rendering. Part of the reason that I only use a single circuit is that I need to copy and paste different parts, and I'm not sure if copying/pasting between different circuits is possible. Also, copy/paste rather often dies on me, especially when selecting multiple components, which makes workflow a bit more complicated. (This happens to me rather often and is really annoying, because the only way to fix it is to close the tab and restart. Symptoms after breakage include inability to copy/paste or move any circuit elements around. If there's any way to submit debug logs for when this happens, feel free to let me know and I'll be sure to try next time it happens. You have my email.)
Exporting via the export tool produces a single PNG file for the entire circuit, where I often need just a bit of the entire diagram. Screenshots let me select a small portion of the circuit.
I'm not entirely sure how this could be fixed. If there were gist-like embeddable widgets, I think the convenience of those would outweigh the disadvantages of a slightly different workflow. Circuit "gists" would be awesome. Another thing that would be great is if I could select a bunch of elements on a circuit, click on some button, and have a new circuit created with only those elements in it. (Note that I'm just brainstorming what would help me specifically, so I don't know how all this might fit into your product.)
Anyway, CircuitLab is awesome! Thanks for making it.