Electronics.SE has a nice WYSIWYG editor, CircuitLab. It allows a user to create an electronics schematic, which is tied in with the Imgur Image upload feature. These schematics can then be edited while editing a post, without having to start from scratch.
I believe Circuit Lab would be useful on DIY.SE, considering how often wiring questions come up.
Per WYSIWYG Image editors for domain-specific QA's? site specific editors are a common change for some Stacks. If the community or the mods see CircuitLab as a useful addition, can this be requested? AFAIK this would require minimal changes by the code team to enable, as it is already supported by the system.
As an example, I used the EE.SE CircuitLab to create (and copy/pasted) the schematic for https://diy.stackexchange.com/a/78848/12387