Return 1 and 2 were great ... until the Ancients simply vanished, off camera, during the span of a single episode, never to be mentioned again.
Pardon me, but that is absurd.
After ten years of SG-1, plus three years of SGA, the legendary, nay mythical Ancients finally make their appearance.
Then they're gone, never to be mentioned again, within the space of a single episode, as if they were victims of a traffic accident along the side of the highway as we drive by.
Were the series writers out of their minds? The Ancients' sudden appearance and even more sudden disappearance wasn't even "lampshaded" with a passing comment.
Example: "I can't believe after all that time, we never even got to know them."
Shouldn't the relationship between earthlings and the Ancients been explored in painstaking detail? Shouldn't it have been given at least as much attention as the relationship between us and the Asgard?