Heh, I think I even know what you mean by "after all the aliens showed up and things started getting interesting". Obviously the entire series is about aliens, but I thought just the Goa'uld on their own were a little boring. Then suddenly they started meeting more aliens, several different races, and there was also some time travel and things like alternate dimensions. That was when I got into it for its own sake rather than just wanting to know what happened before Atlantis. :D