It is confirmed then...
... JJJ (J. Jonah Jameson) was based on Stan Lee.
Said so by J.K. Simmons.
Here: https://www.youtube.com/watch?v=7ubZWJw3m4w
I wondered about this for a long time, and finally there's confirmation. Maybe people on this site knew this, but for myself, it's nice to have this finally settled. I've heard here and there that Stan Lee was difficult to work with.
J.K. Simmons did such a wonderful job in the role.