Network Diagrams?

How do you draw or like to see network diagrams? Do you have any tips for drawing clearer diagrams and are there any industry standard guidelines?

Since starting in networking I've tried to build a clear and logical diagramming style... and wouldn't mind any feedback. Here, for example, are some examples from my home lab. I found early on that separating L2 and L3 really helped clean things up (or is there a better way?), but some of the more complicated parts (especially tunnels, routing protocols, and VRFs) still stump me. Any tips or examples?

I found this excellent packet pushers article, but there doesn't seem to be much else out there. And in my team, everyone has their own style which is nearly unintelligible to anyone else (and, my pet peeve, they don't differentiate L2 and L3).