Wow. Bobby. Thanks for that. That was an interesting read!
Makes me wish even more fervently I for once had a chance to learn darkroom work...
But a question to all here then (which will hijack the thread a little ... and not, maybe, either): I once posted this impromptu photo of
my_sister just because I suddenly saw that side light and liked it and ... well, took the pic. And she looks away from the camera, too. And there is only this one-directional light (one big, big window on the side), too.
Many said back when I first posted the pic that it looked good. Even my sister herself said "Old - but interesting!" about her own photo (

) - but is it all against the cardinal rules of taking portrait pics? (It was not a planned session, though).
Back to this photo.
I feel that what is now declared as "soft focus" was actually once "out of focus". And you seem to have used a very high ISO, and I wonder what your light source was? It cannot have been very light, and it looks like a long exposure was asked for? The light is too one-directional, I think, though I do like when the eyes get lit up like happened here. His skin is too bright, though.
As to what you can do about THIS very photo to make it better: I don't really know.
In the future: add a second light, and maybe diffuse the one light source more? (Just some amateur ideas). Make the child engage with you (us as viewers).