I thought that the planet had some some sort of energy source at the core that provided the power to dial the 9th chevron, something that can't be done just anywhere.It was an evacuation, and he could have dialed anywhere other than Earth (pick a barren planet if you want). Obviously, the nine-chevron address can at least theoretically be dialed from somewhere else (as it was originally supposed to be dialed from Earth). It's not worth putting everybody's lives at risk (including a freaking Senator, dozens of civilians, and an IOA representative).
It actually felt different and fresh when compared to the other Stargate shows yet at the same time it felt as if it was part of the same franchise. A good mix. It also felt dark without crossing into the BSG style omg i want to slit my wrists and shoot myself mode.
, so it may be a reasonable logic jump from that perspective. But I doubt the writers are going down that road.