I enjoyed the first season of Atlantis way more than any of the ones after.
It held so much promise, a whole new galaxy, a whole city to explore, but we got lumbered with the Genii, the most boring enemy ever.
The wraith were interesting but don't seem much of a threat anymore, and the replicators are...not as interesting as they could be.
We rarely see the Stargate, which I miss, as the new DHD looks cool.