Atlantis wasn't all that great, IMHO. They tried to use the same formula that SG-1 used with the teams going out and exploring new worlds but c'mon... you didn't have Carter, O'Neill, Teal'C or Daniel, it didn't have that same strength. The few things that made it great were Rodney McKay (unique, strong character), the tie-ins with the Ancients and it's more Stargate!
But so many things could have been done better... what did they actually ever accomplish? Almost anything they ever achieved was destroyed or lost by the end of the episode...
Oh HEY, real, living Ancients!! Now we get to learn from them!! OH WAIT... Replicators killed them all. Whoa, a cool source of potentially unlimited power for Atlantis? Breaking apart space-time in other realities... bummer dude... WOW, an Ancient SPACESHIP?? Gets destroyed. An Ascension machine? Kills people or fails miserably. An entire colony of ascended people? They ascend without teaching them anything... it goes on and on and on.
Plus, the entire idea of the Wraith... the Ancients were among the greatest races of the Galaxy. SG-1 played them up to be just incredible with their knowledge of science and their advanced physiology allowing them pre-ascension powers... but they were beaten by a race that the humans now can stem the tide of? A race of "life-sucking" vampire aliens? Doesn't make sense.
SG-1 is one of my favorite shows of all time, don't get me wrong. But they learned... Naquadria, Naquada reactors, the X303, X302, they beat the Gould and the Replicators... Daniel ascended, O'Neill had the library of the Ancients downloaded into his mind twice.
Universe was a completely different route. TBH, it was a good sci-fi show, but not Stargate. It was more along the lines of Battlestar Galactica and all the Stargate fans weren't enthralled with it. They enticed everyone with the big "Destiny's mission" then when they revealed it... it was kinda like "oh... that's cool... I guess..."
Just my thoughts... somewhat off-topic as they may be.