Hello, let's work for a better Wikimedia Commons! I usually work on the Korean Wikipedia, where I am an administrator. I am also a VRT-permissions agent and license reviewer here.
I usually use CC-BY-SA 4.0 for my uploads, but if I feel there is significant educational need to remove almost all restricitons, I will use CC-BY or CC0 1.0.
Sometimes, I use the initial J.C., since some of my works have been used in coursework as figures and diagrams. This is to avoid any potential academic integrity investigations: It's my work, not plagiarism! :).
I think sometimes FoP is enforced too broadly. For example, the Korea Copyright Commission [1] states that historical monuments in South Korea don't have copyright and is free, but I still see Korean monuments getting nominated sometimes.