No naquada on Earth.

[Saquist]

That was about the only thing I could attribute to naquadah in Atlantis.
Might that imply that Naquadah is not native to the Pegasus Galaxy?
The Destiny might have seeded this galaxy with the Stargates but might have had it's own supply of naquadah aboard.

[Quadhelix]

Might that imply that Naquadah is not native to the Pegasus Galaxy?

Well, as you pointed out, a ZPM can produce many orders of magnitude more power than a Naquadah generator, so Naquadah might been used only for its superconductive properties.

As for naquadah not being native to Pegasus, that is not entirely out the realm of possibility: since Pegasus is a dwarf galaxy, it's probably very metal-poor, and thus would have even fewer heavy elements like uranium and naquadah.

The Destiny might have seeded this galaxy with the Stargates but might have had it's own supply of naquadah aboard.

Uh...this might not be on topic, but the Destiny isn't the ship seeding Stargates, it's the follow up. That's why the crew spends so much time using the Destiny's Stargate.

Also, there is reason to believe that the Milky Way Stargate network is newer than the Destiny mission, and the Pegasus 'Gate network is even newer than that.