Works as a decent wrap-up, yeah. But I had a (couple? not sure) thoughts.
Firstly, Apollo. Keep the biplane and such, but change it up a bit. The biplane was a gift Zeus bought him, and Apollo went a little... nuts with it. He liked it too much. So at the same time as Demeter vanishes, Apollo starts taking longer, lower joyrides around, and naturally the sun was more intense and hotter in response.
Which, naturally, gives us the Dirty Thirties.
Also, as per the original material, Hades is -everywhere.- Even outside of Hadestown, odds are he owns 45% of anything you see. Zeus is fat and happy in the Ivory City, and can muscle Hades out, but he's also not paying NEAR as much attention as he could be to what's beyond his neat little borders - which is why Hades is such a constant.
And two things about the general feel of the setting: It's dark, but it shouldn't be just dark. More like... bad times are happening, but there's still some cautious optimism in the air for... god knows what reason. I mean, even after Orpheus fails to rescue Eurydice, her and Persephone's "toast" to him is far from hopeless.
Also, I think we should avoid making the powers of the deities too close to their original. Hephaestus is the greatest engineer on the planet and made the train to Hades, yeah, but he isn't the spirit in every iron-working man. Hades has sway over his domain, but he isn't an absolute. Apollo's presence makes the sun stronger and such, but he doesn't literally carry the sun across the sky.
It allows the mystique of these Supermen and Superwomen to exist without giving anyone reason to outright believe they're divine or anything.