A few thoughts on the gods and associated units in no specific order:
Odin giving a buff to ranged units seems odd. He was associated with the nobles, making a cavalry buff much more logical (His prominent horse also seems to make this a clear choice).
The economic buff makes a bit more sense with Thor since he was a god commonly worshipped by lower classes, but I would extend that helping all economic things, not just mining. Perhaps if you are looking for a more flavourful option I'd say that making his heroes more effective at slaying myth units would be a nice one. Most of Thor's myths are about him killing giants in some way.
Heimdall is responsible in Ragnorak for deploying the Einherjar troops, making those units a better option for him. Baldur is only a survivor of the events. I'd advise giving light elves to Baldur since his good looks were famous. Instead of providing more offensive power to units, I think that a defensive bonus would be better given how he was famous for being virtually invincible.
For the Greeks:
Dionysus was associated with satyrs and centaurs, especially the former.
A dryad unit might be a better option for Demeter given her relation to nature.
Hercules was known for having two main weapons, a club and a bow having arrows dipped in the blood of the hydra, making them venomous.
Poseidon would be a better candidate for the minotaur since it was his bull that fathered the creature.
Artemis might be better suited with the Calydonian Boar, which she sent.
Ares seems a better fit for the centaurs given both of their warlike natures.