Your analaysis was super helpful.

About gods, I think it is supposed to be wierd and mysteriouse.
I guess they are the avatars of concepts in reality.
Like, Amaterasu, and very spefici ceremony and seals can summon their power.
I can imagine Mikos, who use chakra, but has diffrent kind of training.
Ninjas can learn Mikojutsu, and the opposite, it isn't their homefield.
They empty theirselves to gain more and more access to the god's power.
Sacrficing yourself summon the god for one action.

Artifacts, like masks can lower the price.


And actually important, because I imagine, that the edge that gave the win for the Sound against thhe forces of Konoha which overwhelmed them in quanity, quality and even morale-
The sound ninjas didn't hesitated to use forbidden jutsus.
Odayama, his wife and her sister for example used forbidden jutsus.

So.discussing forbidden jutsus is quite relevant